Add ImageData-related API to OffscreenCanvasRenderingContext2D

third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.idl

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Note: The official spec is WIP at wiki.whatwg.org/wiki/OffscreenCanvas.
 
 [
     Exposed=(Window,Worker),
     RuntimeEnabled=ExperimentalCanvasFeatures,
 ] interface OffscreenCanvasRenderingContext2D {
@@ skipping 45 matching lines @@
     void translate(unrestricted double x, unrestricted double y);
     void transform(unrestricted double a, unrestricted double b, unrestricted double c, unrestricted double d, unrestricted double e, unrestricted double f);
     void setTransform(unrestricted double a, unrestricted double b, unrestricted double c, unrestricted double d, unrestricted double e, unrestricted double f);
     void resetTransform();
 
     // shadows
     attribute unrestricted double shadowOffsetX;
     attribute unrestricted double shadowOffsetY;
     attribute unrestricted double shadowBlur;
     attribute DOMString shadowColor;
+
+    // pixel manipulation
+    [RaisesException] ImageData createImageData(ImageData imagedata);
+    [RaisesException] ImageData createImageData(double sw, double sh);
+    [RaisesException] ImageData getImageData(double sx, double sy, double sw, double sh);
+    [RaisesException] void putImageData(ImageData imagedata, double dx, double dy);
+    [RaisesException] void putImageData(ImageData imagedata, double dx, double dy, double dirtyX, double dirtyY, double dirtyWidth, double dirtyHeight);
 };
 
 OffscreenCanvasRenderingContext2D implements CanvasPathMethods;