Revert "Add hook into pepper to query if running on the main thread."

This reverts commit r57233

TBR: brettw

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@57235 0039d316-1c4b-4281-b951-d872f2087c98

DEPS

@@ -163,7 +163,7 @@ deps = {
     Var("libvpx_revision"),
 
   "src/third_party/ppapi":
-    "http://ppapi.googlecode.com/svn/trunk@209",
+    "http://ppapi.googlecode.com/svn/trunk@207",
 
   "src/third_party/libjingle/source":
     "http://libjingle.googlecode.com/svn/branches/nextsnap@" +

webkit/glue/plugins/pepper_plugin_module.cc

@@ -120,18 +120,13 @@ void CallOnMainThread(int delay_in_msec,
       delay_in_msec);
 }
 
-bool IsMainThread() {
-  return GetMainThreadMessageLoop()->BelongsToCurrentThread();
-}
-
 const PPB_Core core_interface = {
   &AddRefResource,
   &ReleaseResource,
   &MemAlloc,
   &MemFree,
   &GetTime,
-  &CallOnMainThread,
-  &IsMainThread
+  &CallOnMainThread
 };
 
 // PPB_Testing -----------------------------------------------------------------