Provide shared context to Platform API in renderer.

content/browser/in_process_webkit/browser_webkitplatformsupport_impl.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/in_process_webkit/browser_webkitplatformsupport_impl.h"
 
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "content/browser/gpu/browser_gpu_channel_host_factory.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebData.h"
@@ skipping 102 matching lines @@
   NOTREACHED();
   return WebKit::WebData();
 }
 
 int BrowserWebKitPlatformSupportImpl::databaseDeleteFile(
     const WebKit::WebString& vfs_file_name, bool sync_dir) {
   const base::FilePath path = webkit_base::WebStringToFilePath(vfs_file_name);
   return file_util::Delete(path, false) ? 0 : 1;
 }
 
-GpuChannelHostFactory*
-BrowserWebKitPlatformSupportImpl::GetGpuChannelHostFactory() {
-  return BrowserGpuChannelHostFactory::instance();
+WebKit::WebGraphicsContext3D* BrowserWebKitPlatformSupportImpl::
+    createOffscreenGraphicsContext3D(
+        const WebKit::WebGraphicsContext3D::Attributes& attributes) {
+  NOTREACHED();
+  return NULL;

[jamesr, 2013/03/06 00:26:10]

Why bother overriding this?  Isn't there a default null-returning implementation
somewhere further up the inheritance chain?

[danakj, 2013/03/06 00:27:10]

There is, in the Platform class. This just adds a NOTREACHED() so we know
browser-side shinanigans are happening. I can remove it if you like?

+}
+
+WebKit::WebGraphicsContext3D* BrowserWebKitPlatformSupportImpl::
+     sharedOffscreenGraphicsContext3D() {
+  NOTREACHED();
+  return NULL;
+}
+
+GrContext* BrowserWebKitPlatformSupportImpl::sharedOffscreenGrContext() {
+  NOTREACHED();
+  return NULL;
 }
 
 }  // namespace content