Allow each WGC3D subclass to determine the correct GrGLInterface for its GrContext.

ui/gfx/gl/gl_bindings_skia_in_process.cc

Index: ui/gfx/gl/gl_bindings_skia_in_process.cc
===================================================================
--- ui/gfx/gl/gl_bindings_skia_in_process.cc	(revision 98420)
+++ ui/gfx/gl/gl_bindings_skia_in_process.cc	(working copy)
@@ -469,14 +469,14 @@
 
 namespace gfx {
 
-void BindSkiaToInProcessGL() {
+GrGLInterface* GetInProcessSkiaGLBinding() {
   static SkAutoTUnref<GrGLInterface> host_gl_interface;
   if (NULL == host_gl_interface.get()) {
     GrGLBinding binding;
     switch (gfx::GetGLImplementation()) {
       case gfx::kGLImplementationNone:
         NOTREACHED();
-        return;
+        return NULL;
       case gfx::kGLImplementationDesktopGL:
         binding = kDesktop_GrGLBinding;
         break;
@@ -488,10 +488,10 @@
         break;
       case gfx::kGLImplementationMockGL:
         NOTREACHED();
-        return;
+        return NULL;
       default:
         NOTREACHED();
-        return;
+        return NULL;
     }
 
     GrGLInterface* interface = new GrGLInterface;
@@ -602,7 +602,7 @@
     interface->fBindFragDataLocationIndexed =
       StubBindFragDataLocationIndexedARB;
   }
-  GrGLSetDefaultGLInterface(host_gl_interface.get());
+  return host_gl_interface.get();
 }
 
 }  // namespace gfx