chromium/src/third_party/blink/renderer/modules/canvas/canvas2d/canvas_rendering_context_2d.h - manifest_repos/chromium_src - Git at Google

 /*
  * Copyright (C) 2006, 2007, 2009, 2010, 2011, 2012 Apple Inc. All rights
  * reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_CANVAS_CANVAS2D_CANVAS_RENDERING_CONTEXT_2D_H_
 #define THIRD_PARTY_BLINK_RENDERER_MODULES_CANVAS_CANVAS2D_CANVAS_RENDERING_CONTEXT_2D_H_

 #include <random>

 #include "base/macros.h"
 #include "services/metrics/public/cpp/ukm_recorder.h"
 #include "third_party/blink/renderer/bindings/modules/v8/v8_canvas_formatted_text.h"
 #include "third_party/blink/renderer/bindings/modules/v8/v8_canvas_rendering_context_2d_settings.h"
 #include "third_party/blink/renderer/core/html/canvas/canvas_context_creation_attributes_core.h"
 #include "third_party/blink/renderer/core/html/canvas/canvas_rendering_context.h"
 #include "third_party/blink/renderer/core/html/canvas/canvas_rendering_context_factory.h"
 #include "third_party/blink/renderer/core/html/canvas/image_data.h"
 #include "third_party/blink/renderer/core/style/filter_operations.h"
 #include "third_party/blink/renderer/core/svg/svg_resource_client.h"
 #include "third_party/blink/renderer/modules/canvas/canvas2d/base_rendering_context_2d.h"
 #include "third_party/blink/renderer/modules/canvas/canvas2d/canvas_formatted_text.h"
 #include "third_party/blink/renderer/modules/canvas/canvas2d/canvas_rendering_context_2d_state.h"
 #include "third_party/blink/renderer/modules/canvas/canvas2d/identifiability_study_helper.h"
 #include "third_party/blink/renderer/modules/modules_export.h"
 #include "third_party/blink/renderer/platform/bindings/exception_state.h"
 #include "third_party/blink/renderer/platform/bindings/script_wrappable.h"
 #include "third_party/blink/renderer/platform/graphics/graphics_types.h"
 #include "third_party/blink/renderer/platform/heap/garbage_collected.h"
 #include "third_party/blink/renderer/platform/privacy_budget/identifiability_digest_helpers.h"
 #include "third_party/blink/renderer/platform/scheduler/public/thread.h"
 #include "third_party/blink/renderer/platform/wtf/linked_hash_set.h"
 #include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

 namespace cc {
 class Layer;
 }

 namespace blink {

 class CanvasImageSource;
 class Element;
 class ExceptionState;
 class Font;
 class HitRegion;
 class HitRegionOptions;
 class HitRegionManager;
 class HitTestCanvasResult;
 class Path2D;
 class TextMetrics;

 using CanvasImageSourceUnion =
     CSSImageValueOrHTMLImageElementOrSVGImageElementOrHTMLVideoElementOrHTMLCanvasElementOrImageBitmapOrOffscreenCanvasOrVideoFrame;

 class MODULES_EXPORT CanvasRenderingContext2D final
     : public CanvasRenderingContext,
       public BaseRenderingContext2D,
       public SVGResourceClient {
   DEFINE_WRAPPERTYPEINFO();

  public:
   class Factory : public CanvasRenderingContextFactory {
    public:
     Factory() = default;
     ~Factory() override = default;

     CanvasRenderingContext* Create(
         CanvasRenderingContextHost* host,
         const CanvasContextCreationAttributesCore& attrs) override;

     CanvasRenderingContext::ContextType GetContextType() const override {
       return CanvasRenderingContext::kContext2D;
     }

    private:
     DISALLOW_COPY_AND_ASSIGN(Factory);
   };

   CanvasRenderingContext2D(HTMLCanvasElement*,
                            const CanvasContextCreationAttributesCore&);
   ~CanvasRenderingContext2D() override;

   HTMLCanvasElement* canvas() const {
     DCHECK(!Host() || !Host()->IsOffscreenCanvas());
     return static_cast<HTMLCanvasElement*>(Host());
   }
   void SetCanvasGetContextResult(RenderingContext&) final;

   bool isContextLost() const override;

   bool ShouldAntialias() const override;
   void SetShouldAntialias(bool) override;

   void scrollPathIntoView();
   void scrollPathIntoView(Path2D*);

   void clearRect(double x, double y, double width, double height);
   void ClearRect(double x, double y, double width, double height) override {
     clearRect(x, y, width, height);
   }

   void Reset() override;

   String font() const;
   void setFont(const String&) override;

   String direction() const;
   void setDirection(const String&);

   void setTextLetterSpacing(const double letter_spacing);
   void setTextWordSpacing(const double word_spacing);
   void setTextRendering(const String&);

   void setFontKerning(const String&);
   void setFontStretch(const String&);
   void setFontVariantCaps(const String&);

   void fillText(const String& text, double x, double y);
   void fillText(const String& text, double x, double y, double max_width);
   void strokeText(const String& text, double x, double y);
   void strokeText(const String& text, double x, double y, double max_width);
   TextMetrics* measureText(const String& text);

   CanvasRenderingContext2DSettings* getContextAttributes() const;

   void fillFormattedText(CanvasFormattedText* formatted_text,
                          double x,
                          double y,
                          double wrap_width);

   void drawFocusIfNeeded(Element*);
   void drawFocusIfNeeded(Path2D*, Element*);

   void addHitRegion(const HitRegionOptions*, ExceptionState&);
   void removeHitRegion(const String& id);
   void clearHitRegions();
   HitRegion* HitRegionAtPoint(const FloatPoint&);
   unsigned HitRegionsCount() const override;

   void LoseContext(LostContextMode) override;
   void DidSetSurfaceSize() override;

   void RestoreCanvasMatrixClipStack(cc::PaintCanvas*) const override;

   // TaskObserver implementation
   void DidProcessTask(const base::PendingTask&) final;

   void StyleDidChange(const ComputedStyle* old_style,
                       const ComputedStyle& new_style) override;
   HitTestCanvasResult* GetControlAndIdIfHitRegionExists(
       const PhysicalOffset& location) override;
   String GetIdFromControl(const Element*) override;

   // SVGResourceClient implementation
   void ResourceContentChanged(SVGResource*) override;

   void UpdateFilterReferences(const FilterOperations&);
   void ClearFilterReferences();

   // BaseRenderingContext2D implementation
   bool OriginClean() const final;
   void SetOriginTainted() final;
   bool WouldTaintOrigin(CanvasImageSource* source) final {
     return CanvasRenderingContext::WouldTaintOrigin(source);
   }
   void DisableAcceleration() override;

   int Width() const final;
   int Height() const final;

   bool CanCreateCanvas2dResourceProvider() const final;

   RespectImageOrientationEnum RespectImageOrientation() const final;

   bool ParseColorOrCurrentColor(Color&, const String& color_string) const final;

   cc::PaintCanvas* GetOrCreatePaintCanvas() final;
   cc::PaintCanvas* GetPaintCanvas() const final;

   void DidDraw(const SkIRect& dirty_rect) final;
   scoped_refptr<StaticBitmapImage> GetImage() final;

   bool StateHasFilter() final;
   sk_sp<PaintFilter> StateGetFilter() final;
   void SnapshotStateForFilter() final;

   void ValidateStateStackWithCanvas(const cc::PaintCanvas*) const final;

   void FinalizeFrame() override;

   bool IsPaintable() const final {
     return canvas() && canvas()->GetCanvas2DLayerBridge();
   }

   void WillDrawImage(CanvasImageSource*) const final;

   void Trace(Visitor*) const override;

   ImageData* getImageDataInternal(int sx,
                                   int sy,
                                   int sw,
                                   int sh,
                                   ImageDataSettings*,
                                   ExceptionState&) final;

   CanvasColorParams ColorParamsForTest() const {
     return GetCanvas2DColorParams();
   }

   IdentifiableToken IdentifiableTextToken() const override {
     return identifiability_study_helper_.GetToken();
   }

   bool IdentifiabilityEncounteredSkippedOps() const override {
     return identifiability_study_helper_.encountered_skipped_ops();
   }

   bool IdentifiabilityEncounteredSensitiveOps() const override {
     return identifiability_study_helper_.encountered_sensitive_ops();
   }

  protected:
   CanvasColorParams GetCanvas2DColorParams() const override;
   bool WritePixels(const SkImageInfo& orig_info,
                    const void* pixels,
                    size_t row_bytes,
                    int x,
                    int y) override;
   void WillOverwriteCanvas() override;

  private:
   friend class CanvasRenderingContext2DAutoRestoreSkCanvas;

   void DispatchContextLostEvent(TimerBase*);
   void DispatchContextRestoredEvent(TimerBase*);
   void TryRestoreContextEvent(TimerBase*);

   void PruneLocalFontCache(size_t target_size);

   void ScrollPathIntoViewInternal(const Path&);

   void DrawTextInternal(const String&,
                         double x,
                         double y,
                         CanvasRenderingContext2DState::PaintType,
                         double* max_width = nullptr);

   const Font& AccessFont();

   void DrawFocusIfNeededInternal(const Path&, Element*);
   bool FocusRingCallIsValid(const Path&, Element*);
   void DrawFocusRing(const Path&);
   void UpdateElementAccessibility(const Path&, Element*);

   CanvasRenderingContext::ContextType GetContextType() const override {
     return CanvasRenderingContext::kContext2D;
   }

   bool IsRenderingContext2D() const override { return true; }
   bool IsComposited() const override;
   bool IsAccelerated() const override;
   bool IsOriginTopLeft() const override;
   bool HasAlpha() const override { return CreationAttributes().alpha; }
   bool IsDesynchronized() const override {
     return CreationAttributes().desynchronized;
   }
   void SetIsInHiddenPage(bool) override;
   void SetIsBeingDisplayed(bool) override;
   void Stop() final;

   bool IsTransformInvertible() const override;
   TransformationMatrix GetTransform() const override;

   cc::Layer* CcLayer() const override;
   bool IsCanvas2DBufferValid() const override;

   Member<HitRegionManager> hit_region_manager_;
   LostContextMode context_lost_mode_;
   bool context_restorable_;
   unsigned try_restore_context_attempt_count_;
   HeapTaskRunnerTimer<CanvasRenderingContext2D>
       dispatch_context_lost_event_timer_;
   HeapTaskRunnerTimer<CanvasRenderingContext2D>
       dispatch_context_restored_event_timer_;
   HeapTaskRunnerTimer<CanvasRenderingContext2D>
       try_restore_context_event_timer_;

   FilterOperations filter_operations_;
   HashMap<String, FontDescription> fonts_resolved_using_current_style_;
   bool should_prune_local_font_cache_;
   LinkedHashSet<String> font_lru_list_;

   static constexpr float kRasterMetricProbability = 0.01;
   std::mt19937 random_generator_;
   std::bernoulli_distribution bernoulli_distribution_;

   ukm::UkmRecorder* ukm_recorder_;
   ukm::SourceId ukm_source_id_;
 };

 }  // namespace blink

 #endif  // THIRD_PARTY_BLINK_RENDERER_MODULES_CANVAS_CANVAS2D_CANVAS_RENDERING_CONTEXT_2D_H_
	/*
	* Copyright (C) 2006, 2007, 2009, 2010, 2011, 2012 Apple Inc. All rights
	* reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
	* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#ifndef THIRD_PARTY_BLINK_RENDERER_MODULES_CANVAS_CANVAS2D_CANVAS_RENDERING_CONTEXT_2D_H_
	#define THIRD_PARTY_BLINK_RENDERER_MODULES_CANVAS_CANVAS2D_CANVAS_RENDERING_CONTEXT_2D_H_

	#include <random>

	#include "base/macros.h"
	#include "services/metrics/public/cpp/ukm_recorder.h"
	#include "third_party/blink/renderer/bindings/modules/v8/v8_canvas_formatted_text.h"
	#include "third_party/blink/renderer/bindings/modules/v8/v8_canvas_rendering_context_2d_settings.h"
	#include "third_party/blink/renderer/core/html/canvas/canvas_context_creation_attributes_core.h"
	#include "third_party/blink/renderer/core/html/canvas/canvas_rendering_context.h"
	#include "third_party/blink/renderer/core/html/canvas/canvas_rendering_context_factory.h"
	#include "third_party/blink/renderer/core/html/canvas/image_data.h"
	#include "third_party/blink/renderer/core/style/filter_operations.h"
	#include "third_party/blink/renderer/core/svg/svg_resource_client.h"
	#include "third_party/blink/renderer/modules/canvas/canvas2d/base_rendering_context_2d.h"
	#include "third_party/blink/renderer/modules/canvas/canvas2d/canvas_formatted_text.h"
	#include "third_party/blink/renderer/modules/canvas/canvas2d/canvas_rendering_context_2d_state.h"
	#include "third_party/blink/renderer/modules/canvas/canvas2d/identifiability_study_helper.h"
	#include "third_party/blink/renderer/modules/modules_export.h"
	#include "third_party/blink/renderer/platform/bindings/exception_state.h"
	#include "third_party/blink/renderer/platform/bindings/script_wrappable.h"
	#include "third_party/blink/renderer/platform/graphics/graphics_types.h"
	#include "third_party/blink/renderer/platform/heap/garbage_collected.h"
	#include "third_party/blink/renderer/platform/privacy_budget/identifiability_digest_helpers.h"
	#include "third_party/blink/renderer/platform/scheduler/public/thread.h"
	#include "third_party/blink/renderer/platform/wtf/linked_hash_set.h"
	#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"

	namespace cc {
	class Layer;
	}

	namespace blink {

	class CanvasImageSource;
	class Element;
	class ExceptionState;
	class Font;
	class HitRegion;
	class HitRegionOptions;
	class HitRegionManager;
	class HitTestCanvasResult;
	class Path2D;
	class TextMetrics;

	using CanvasImageSourceUnion =
	CSSImageValueOrHTMLImageElementOrSVGImageElementOrHTMLVideoElementOrHTMLCanvasElementOrImageBitmapOrOffscreenCanvasOrVideoFrame;

	class MODULES_EXPORT CanvasRenderingContext2D final
	: public CanvasRenderingContext,
	public BaseRenderingContext2D,
	public SVGResourceClient {
	DEFINE_WRAPPERTYPEINFO();

	public:
	class Factory : public CanvasRenderingContextFactory {
	public:
	Factory() = default;
	~Factory() override = default;

	CanvasRenderingContext* Create(
	CanvasRenderingContextHost* host,
	const CanvasContextCreationAttributesCore& attrs) override;

	CanvasRenderingContext::ContextType GetContextType() const override {
	return CanvasRenderingContext::kContext2D;
	}

	private:
	DISALLOW_COPY_AND_ASSIGN(Factory);
	};

	CanvasRenderingContext2D(HTMLCanvasElement*,
	const CanvasContextCreationAttributesCore&);
	~CanvasRenderingContext2D() override;

	HTMLCanvasElement* canvas() const {
	DCHECK(!Host() \|\| !Host()->IsOffscreenCanvas());
	return static_cast<HTMLCanvasElement*>(Host());
	}
	void SetCanvasGetContextResult(RenderingContext&) final;

	bool isContextLost() const override;

	bool ShouldAntialias() const override;
	void SetShouldAntialias(bool) override;

	void scrollPathIntoView();
	void scrollPathIntoView(Path2D*);

	void clearRect(double x, double y, double width, double height);
	void ClearRect(double x, double y, double width, double height) override {
	clearRect(x, y, width, height);
	}

	void Reset() override;

	String font() const;
	void setFont(const String&) override;

	String direction() const;
	void setDirection(const String&);

	void setTextLetterSpacing(const double letter_spacing);
	void setTextWordSpacing(const double word_spacing);
	void setTextRendering(const String&);

	void setFontKerning(const String&);
	void setFontStretch(const String&);
	void setFontVariantCaps(const String&);

	void fillText(const String& text, double x, double y);
	void fillText(const String& text, double x, double y, double max_width);
	void strokeText(const String& text, double x, double y);
	void strokeText(const String& text, double x, double y, double max_width);
	TextMetrics* measureText(const String& text);

	CanvasRenderingContext2DSettings* getContextAttributes() const;

	void fillFormattedText(CanvasFormattedText* formatted_text,
	double x,
	double y,
	double wrap_width);

	void drawFocusIfNeeded(Element*);
	void drawFocusIfNeeded(Path2D, Element);

	void addHitRegion(const HitRegionOptions*, ExceptionState&);
	void removeHitRegion(const String& id);
	void clearHitRegions();
	HitRegion* HitRegionAtPoint(const FloatPoint&);
	unsigned HitRegionsCount() const override;

	void LoseContext(LostContextMode) override;
	void DidSetSurfaceSize() override;

	void RestoreCanvasMatrixClipStack(cc::PaintCanvas*) const override;

	// TaskObserver implementation
	void DidProcessTask(const base::PendingTask&) final;

	void StyleDidChange(const ComputedStyle* old_style,
	const ComputedStyle& new_style) override;
	HitTestCanvasResult* GetControlAndIdIfHitRegionExists(
	const PhysicalOffset& location) override;
	String GetIdFromControl(const Element*) override;

	// SVGResourceClient implementation
	void ResourceContentChanged(SVGResource*) override;

	void UpdateFilterReferences(const FilterOperations&);
	void ClearFilterReferences();

	// BaseRenderingContext2D implementation
	bool OriginClean() const final;
	void SetOriginTainted() final;
	bool WouldTaintOrigin(CanvasImageSource* source) final {
	return CanvasRenderingContext::WouldTaintOrigin(source);
	}
	void DisableAcceleration() override;

	int Width() const final;
	int Height() const final;

	bool CanCreateCanvas2dResourceProvider() const final;

	RespectImageOrientationEnum RespectImageOrientation() const final;

	bool ParseColorOrCurrentColor(Color&, const String& color_string) const final;

	cc::PaintCanvas* GetOrCreatePaintCanvas() final;
	cc::PaintCanvas* GetPaintCanvas() const final;

	void DidDraw(const SkIRect& dirty_rect) final;
	scoped_refptr<StaticBitmapImage> GetImage() final;

	bool StateHasFilter() final;
	sk_sp<PaintFilter> StateGetFilter() final;
	void SnapshotStateForFilter() final;

	void ValidateStateStackWithCanvas(const cc::PaintCanvas*) const final;

	void FinalizeFrame() override;

	bool IsPaintable() const final {
	return canvas() && canvas()->GetCanvas2DLayerBridge();
	}

	void WillDrawImage(CanvasImageSource*) const final;

	void Trace(Visitor*) const override;

	ImageData* getImageDataInternal(int sx,
	int sy,
	int sw,
	int sh,
	ImageDataSettings*,
	ExceptionState&) final;

	CanvasColorParams ColorParamsForTest() const {
	return GetCanvas2DColorParams();
	}

	IdentifiableToken IdentifiableTextToken() const override {
	return identifiability_study_helper_.GetToken();
	}

	bool IdentifiabilityEncounteredSkippedOps() const override {
	return identifiability_study_helper_.encountered_skipped_ops();
	}

	bool IdentifiabilityEncounteredSensitiveOps() const override {
	return identifiability_study_helper_.encountered_sensitive_ops();
	}

	protected:
	CanvasColorParams GetCanvas2DColorParams() const override;
	bool WritePixels(const SkImageInfo& orig_info,
	const void* pixels,
	size_t row_bytes,
	int x,
	int y) override;
	void WillOverwriteCanvas() override;

	private:
	friend class CanvasRenderingContext2DAutoRestoreSkCanvas;

	void DispatchContextLostEvent(TimerBase*);
	void DispatchContextRestoredEvent(TimerBase*);
	void TryRestoreContextEvent(TimerBase*);

	void PruneLocalFontCache(size_t target_size);

	void ScrollPathIntoViewInternal(const Path&);

	void DrawTextInternal(const String&,
	double x,
	double y,
	CanvasRenderingContext2DState::PaintType,
	double* max_width = nullptr);

	const Font& AccessFont();

	void DrawFocusIfNeededInternal(const Path&, Element*);
	bool FocusRingCallIsValid(const Path&, Element*);
	void DrawFocusRing(const Path&);
	void UpdateElementAccessibility(const Path&, Element*);

	CanvasRenderingContext::ContextType GetContextType() const override {
	return CanvasRenderingContext::kContext2D;
	}

	bool IsRenderingContext2D() const override { return true; }
	bool IsComposited() const override;
	bool IsAccelerated() const override;
	bool IsOriginTopLeft() const override;
	bool HasAlpha() const override { return CreationAttributes().alpha; }
	bool IsDesynchronized() const override {
	return CreationAttributes().desynchronized;
	}
	void SetIsInHiddenPage(bool) override;
	void SetIsBeingDisplayed(bool) override;
	void Stop() final;

	bool IsTransformInvertible() const override;
	TransformationMatrix GetTransform() const override;

	cc::Layer* CcLayer() const override;
	bool IsCanvas2DBufferValid() const override;

	Member<HitRegionManager> hit_region_manager_;
	LostContextMode context_lost_mode_;
	bool context_restorable_;
	unsigned try_restore_context_attempt_count_;
	HeapTaskRunnerTimer<CanvasRenderingContext2D>
	dispatch_context_lost_event_timer_;
	HeapTaskRunnerTimer<CanvasRenderingContext2D>
	dispatch_context_restored_event_timer_;
	HeapTaskRunnerTimer<CanvasRenderingContext2D>
	try_restore_context_event_timer_;

	FilterOperations filter_operations_;
	HashMap<String, FontDescription> fonts_resolved_using_current_style_;
	bool should_prune_local_font_cache_;
	LinkedHashSet<String> font_lru_list_;

	static constexpr float kRasterMetricProbability = 0.01;
	std::mt19937 random_generator_;
	std::bernoulli_distribution bernoulli_distribution_;

	ukm::UkmRecorder* ukm_recorder_;
	ukm::SourceId ukm_source_id_;
	};

	} // namespace blink

	#endif // THIRD_PARTY_BLINK_RENDERER_MODULES_CANVAS_CANVAS2D_CANVAS_RENDERING_CONTEXT_2D_H_