Provide shared context to Platform API in renderer.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 975e13ec35cacd44864906732b0242d882a1e803..def32598ab7c67ac764c96982393041406a6139b 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -14,6 +14,7 @@
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
+#include "base/memory/weak_ptr.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/stats_table.h"
@@ -98,6 +99,7 @@
 #include "ui/base/ui_base_switches.h"
 #include "v8/include/v8.h"
 #include "webkit/glue/webkit_glue.h"
+#include "webkit/gpu/webgraphicscontext3d_in_process_impl.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
@@ -281,12 +283,16 @@ RenderThreadImpl* RenderThreadImpl::current() {
 
 // When we run plugins in process, we actually run them on the render thread,
 // which means that we need to make the render thread pump UI events.
-RenderThreadImpl::RenderThreadImpl() {
+RenderThreadImpl::RenderThreadImpl()
+    : ALLOW_THIS_IN_INITIALIZER_LIST(shared_context_main_thread_(this)),
+      ALLOW_THIS_IN_INITIALIZER_LIST(shared_context_compositor_thread_(this)) {
   Init();
 }
 
 RenderThreadImpl::RenderThreadImpl(const std::string& channel_name)
-    : ChildThread(channel_name) {
+    : ChildThread(channel_name),
+      shared_context_main_thread_(this),
+      shared_context_compositor_thread_(this) {
   Init();
 }
 
@@ -1124,6 +1130,45 @@ GpuChannelHost* RenderThreadImpl::EstablishGpuChannelSync(
   return GetGpuChannel();
 }
 
+WebKit::WebGraphicsContext3D* RenderThreadImpl::
+     OffscreenContext3dForMainThread() {
+  DCHECK(IsMainThread());
+  return shared_context_main_thread_.Context3d();
+}
+WebKit::WebGraphicsContext3D* RenderThreadImpl::
+    OffscreenContext3dForCompositorThread() {
+  DCHECK(IsMainThread());
+  return shared_context_compositor_thread_.Context3d();
+}
+
+GrContext* RenderThreadImpl::OffscreenGrContextForMainThread() {
+  DCHECK(IsMainThread());
+  return shared_context_main_thread_.GrContext();
+}
+
+GrContext* RenderThreadImpl::OffscreenGrContextForCompositorThread() {
+  DCHECK(IsMainThread());
+  return shared_context_compositor_thread_.GrContext();
+}
+
+WebKit::WebGraphicsContext3D* RenderThreadImpl::CreateOffscreenContext() {
+  WebKit::WebGraphicsContext3D::Attributes attributes;
+  attributes.shareResources = true;
+  attributes.depth = false;
+  attributes.stencil = false;
+  attributes.antialias = false;
+  attributes.noAutomaticFlushes = true;
+
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kInProcessWebGL)) {
+    return webkit::gpu::WebGraphicsContext3DInProcessImpl::CreateForWebView(
+            attributes, false);
+  }
+
+  GURL url("chrome://gpu/RenderThreadImpl::CreateOffscreenContext");
+  return WebGraphicsContext3DCommandBufferImpl::CreateOffscreenContext(
+      this, attributes, url);
+}
+
 WebKit::WebMediaStreamCenter* RenderThreadImpl::CreateMediaStreamCenter(
     WebKit::WebMediaStreamCenterClient* client) {
 #if defined(OS_ANDROID)