Implementation of 2D canvas context lost/restored events

Source/core/html/canvas/CanvasRenderingContext2D.idl

 /*
  * Copyright (C) 2006 Apple Computer, 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
@@ skipping 79 matching lines @@
     boolean isPointInStroke(float x, float y);
     [RuntimeEnabled=ExperimentalCanvasFeatures, RaisesException] boolean isPointInStroke(Path2D? path, float x, float y);
 
     // text
     attribute DOMString font;
     attribute DOMString textAlign;
     attribute DOMString textBaseline;
 
     TextMetrics measureText(DOMString text);
 
+    // Context state
+    // Should be merged with WebGL counterpart in CanvasRenderingContext, once no-longer experimental
+    [RuntimeEnabled=ExperimentalCanvasFeatures] boolean isContextLost();
+
     // other
 
     void setAlpha(float alpha);
     void setCompositeOperation(DOMString compositeOperation);
 
     void setLineWidth(float width);
     void setLineCap(DOMString cap);
     void setLineJoin(DOMString join);
     void setMiterLimit(float limit);
 
@@ skipping 56 matching lines @@
     [RuntimeEnabled=ExperimentalCanvasFeatures] void drawFocusIfNeeded(Element element);
     [RuntimeEnabled=ExperimentalCanvasFeatures] boolean drawCustomFocusRing(Element element);
 
     [ImplementedAs=imageSmoothingEnabled, MeasureAs=PrefixedImageSmoothingEnabled] attribute boolean webkitImageSmoothingEnabled;
     [MeasureAs=UnprefixedImageSmoothingEnabled] attribute boolean imageSmoothingEnabled;
 
     Canvas2DContextAttributes getContextAttributes();
 };
 
 CanvasRenderingContext2D implements CanvasPathMethods;