Disable accelerated 2D canvas on DX9 by not initializing GraphicsContext3D if it can be lost.

chrome/renderer/webgraphicscontext3d_command_buffer_impl.cc

 // Copyright (c) 2010 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.
 
 #if defined(ENABLE_GPU)
 
 #include "chrome/renderer/webgraphicscontext3d_command_buffer_impl.h"
 
 #include <GLES2/gl2.h>
 #ifndef GL_GLEXT_PROTOTYPES
@@ skipping 69 matching lines @@
   const int sample_buffers = attributes.antialias ? 1 : 0;
   const int32 attribs[] = {
     ggl::GGL_ALPHA_SIZE, alpha_size,
     ggl::GGL_DEPTH_SIZE, depth_size,
     ggl::GGL_STENCIL_SIZE, stencil_size,
     ggl::GGL_SAMPLES, samples,
     ggl::GGL_SAMPLE_BUFFERS, sample_buffers,
     ggl::GGL_NONE,
   };
 
+  if (attributes.canRecoverFromContextLoss == false) {

[jamesr, 2010/11/10 21:22:01]

nit: if (!attributes.canRecoverFromContextLoss)

+    GPUInfo gpu_info = host->gpu_info();
+    if (gpu_info.can_lose_context())
+        return false;
+  }
+
   if (render_directly_to_web_view) {
     RenderView* renderview = RenderView::FromWebView(web_view);
     if (!renderview)
       return false;
     gfx::NativeViewId view_id;
 #if !defined(OS_MACOSX)
     view_id = renderview->host_window();
 #else
     plugin_handle_ = renderview->AllocateFakePluginWindowHandle(
         /*opaque=*/true, /*root=*/true);
@@ skipping 921 matching lines @@
 }
 
 void WebGraphicsContext3DCommandBufferImpl::copyTextureToCompositor(
     unsigned texture, unsigned parentTexture) {
   makeContextCurrent();
   glCopyTextureToParentTexture(texture, parentTexture);
   glFlush();
 }
 
 #endif  // defined(ENABLE_GPU)