Add the necessary plumbing mechanisms to ensure proper WebGL support inside the <browser> tag, whic…

ppapi/thunk/ppb_graphics_3d_thunk.cc

Index: ppapi/thunk/ppb_graphics_3d_thunk.cc
diff --git a/ppapi/thunk/ppb_graphics_3d_thunk.cc b/ppapi/thunk/ppb_graphics_3d_thunk.cc
index edc19caae07710c4c1750b14269850496f0a42de..e6ce929482b206f654a3875f19258ddf3ca75dfe 100644
--- a/ppapi/thunk/ppb_graphics_3d_thunk.cc
+++ b/ppapi/thunk/ppb_graphics_3d_thunk.cc
@@ -29,8 +29,17 @@ PP_Resource Create(PP_Instance instance,
   EnterResourceCreation enter(instance);
   if (enter.failed())
     return 0;
+
+  PPB_Graphics3D_API* share_api = NULL;
+  if (share_context) {
+    EnterResourceNoLock<PPB_Graphics3D_API> enter_share(instance, true);
+    if (enter_share.failed())
+      return 0;
+    share_api = enter_share.object();
+  }
+
   return enter.functions()->CreateGraphics3D(
-      instance, share_context, attrib_list);
+      instance, share_api, attrib_list);
 }
 
 PP_Bool IsGraphics3D(PP_Resource resource) {