Share Group plumbing in Blink; Remove WebGL from default share group

Source/core/html/canvas/WebGLContextAttributes.cpp

 /*
  * Copyright (c) 2010, 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:
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
  * copyright notice, this list of conditions and the following disclaimer
@@ skipping 141 matching lines @@
     attrs.stencil = m_stencil;
     attrs.antialias = m_antialias;
     if (m_antialias) {
         if (settings && !settings->openGLMultisamplingEnabled())
             attrs.antialias = false;
     }
     attrs.premultipliedAlpha = m_premultipliedAlpha;
     attrs.failIfMajorPerformanceCaveat = m_failIfMajorPerformanceCaveat;
 
     attrs.noExtensions = true;
-    attrs.shareResources = true;
+    attrs.shareResources = false;
     attrs.preferDiscreteGPU = true;
 
     attrs.topDocumentURL = topDocumentURL;
 
     return attrs;
 }
 
 } // namespace WebCore