Revert of cc: Implement shared worker contexts.

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index 7cff9fe11725baf1e33deab37b21a4cf864af0bc..8997a58307d4207416a25d7e8cc9e1a9b69e6467 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -1018,9 +1018,10 @@
       // Cause the compositor to wait and try again.
       return scoped_ptr<cc::OutputSurface>();
     }
-    worker_context_provider =
-        RenderThreadImpl::current()->SharedWorkerContextProvider();
-    if (!worker_context_provider) {
+
+    worker_context_provider = ContextProviderCommandBuffer::Create(
+        CreateGraphicsContext3D(false), RENDER_WORKER_CONTEXT);
+    if (!worker_context_provider.get()) {
       // Cause the compositor to wait and try again.
       return scoped_ptr<cc::OutputSurface>();
     }