Use newImageSnapshot() to get an image from a Canvas

Source/platform/graphics/GraphicsContext.cpp

 /*
  * Copyright (C) 2003, 2004, 2005, 2006, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Google 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
@@ skipping 249 matching lines @@
 void GraphicsContext::setStrokePattern(PassRefPtr<Pattern> pattern)
 {
     if (contextDisabled())
         return;
 
     ASSERT(pattern);
     if (!pattern) {
         setStrokeColor(Color::black);
         return;
     }
-    mutableState()->setStrokePattern(pattern);
+
+    SkShader::ShaderLocation preferredLocation = isAccelerated() ? SkShader::kGPU_ShaderLocation : SkShader::kCPU_ShaderLocation;
+
+    mutableState()->setStrokePattern(pattern, preferredLocation);
 }
 
 void GraphicsContext::setStrokeGradient(PassRefPtr<Gradient> gradient)
 {
     if (contextDisabled())
         return;
 
     ASSERT(gradient);
     if (!gradient) {
         setStrokeColor(Color::black);
         return;
     }
     mutableState()->setStrokeGradient(gradient);
 }
 
 void GraphicsContext::setFillPattern(PassRefPtr<Pattern> pattern)
 {
     if (contextDisabled())
         return;
 
     ASSERT(pattern);
     if (!pattern) {
         setFillColor(Color::black);
         return;
     }
 
-    mutableState()->setFillPattern(pattern);
+    SkShader::ShaderLocation preferredLocation = isAccelerated() ? SkShader::kGPU_ShaderLocation : SkShader::kCPU_ShaderLocation;
+
+    mutableState()->setFillPattern(pattern, preferredLocation);
 }
 
 void GraphicsContext::setFillGradient(PassRefPtr<Gradient> gradient)
 {
     if (contextDisabled())
         return;
 
     ASSERT(gradient);
     if (!gradient) {
         setFillColor(Color::black);
@@ skipping 1593 matching lines @@
         // FIXME: This is to not break tests (it results in the filter bitmap flag
         // being set to true). We need to decide if we respect InterpolationNone
         // being returned from computeInterpolationQuality.
         resampling = InterpolationLow;
     }
     resampling = limitInterpolationQuality(this, resampling);
     paint->setFilterLevel(static_cast<SkPaint::FilterLevel>(resampling));
 }
 
 }