Update to Chromium revision b0aa1fb5 (#296183).

- Restore CefRenderHandler::OnScrollOffsetChanged.
- Add new RT_PING and RT_SERVICE_WORKER resource type values.
- The resource type for image sub-resource loads has changed from RT_IMAGE to RT_PREFETCH (this is a regression, see http://crbug.com/415253#c23).
- Add a patch to fix a crash in Scheduler::swapQueuesRunPendingTasks* (http://crbug.com/415478).
- Add documentation for cef_key_event_type_t values.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@1846 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef_dll/base/cef_callback_internal.cc

@@ -9,10 +9,6 @@
 namespace base {
 namespace internal {
 
-bool CallbackBase::is_null() const {
-  return bind_state_.get() == NULL;
-}
-
 void CallbackBase::Reset() {
   polymorphic_invoke_ = NULL;
   // NULL the bind_state_ last, since it may be holding the last ref to whatever