Change WGC3DInProcessCBImpl factories to return a base class pointer.

webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc

Index: webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
diff --git a/webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc b/webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
index 2789b0f9ca5b4e11f92b6de26c0a50322527e141..b4170525d4a25f10a4c3ef8929cc0e00297ed484 100644
--- a/webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
+++ b/webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc
@@ -54,7 +54,7 @@ void OnSignalSyncPoint(
 }  // namespace anonymous
 
 // static
-WebGraphicsContext3DInProcessCommandBufferImpl*
+WebKit::WebGraphicsContext3D*
 WebGraphicsContext3DInProcessCommandBufferImpl::CreateViewContext(
     const WebKit::WebGraphicsContext3D::Attributes& attributes,
     gfx::AcceleratedWidget window) {
@@ -65,7 +65,7 @@ WebGraphicsContext3DInProcessCommandBufferImpl::CreateViewContext(
 }
 
 // static
-WebGraphicsContext3DInProcessCommandBufferImpl*
+WebKit::WebGraphicsContext3D*
 WebGraphicsContext3DInProcessCommandBufferImpl::CreateOffscreenContext(
     const WebKit::WebGraphicsContext3D::Attributes& attributes) {
   return new WebGraphicsContext3DInProcessCommandBufferImpl(