Update to Chromium revision 304f01a1 (#358063)

- Improve ordering of CefLoadHandler callbacks. OnLoadingStateChange will
  be called before and after all calls to OnLoadStart and OnLoadEnd.
  OnLoadStart/OnLoadEnd calls will occur as matching pairs
  (see http://crbug.com/539952#c2).
- Remove the |requesting_url| argument to CefGeolocationHandler::
  OnCancelGeolocationPermission. Clients can use the |request_id| argument
  to track this information themselves.
- Fix a crash when loading the PDF extension in multiple browsers with a
  custom CefRequestContext (issue #1757).

libcef/browser/trace_impl.cc

@@ -48,5 +48,5 @@ bool CefEndTracing(const CefString& tracing_file,
 }
 
 int64 CefNowFromSystemTraceTime() {
-  return base::TraceTicks::Now().ToInternalValue();
+  return base::TimeTicks::Now().ToInternalValue();
 }