Update to Chromium revision 0bfd25d4 (#381305)

- Delete include/cef_runnable.h (issue #1336).
- Build the cef_unittests target using all Chromium headers. Add a
  USING_CHROMIUM_INCLUDES define and libcef_dll_wrapper_unittests
  target to support this. This change avoids compile errors due to
  the divergence of CEF and Chromium base/ header implementations.
  The libcef_dll_wrapper sources must now compile successfully with
  both CEF and Chromium base/ headers (issue #1632).
- The onbeforeunload message specified via JavaScript is no longer
  passed to the client (see http://crbug.com/587940).

libcef/browser/native/javascript_dialog_runner_win.cc

@@ -52,7 +52,7 @@ INT_PTR CALLBACK CefJavaScriptDialogRunnerWin::DialogProc(
               GetWindowLongPtr(dialog, DWLP_USER));
       base::string16 user_input;
       bool finish = false;
-      bool result;
+      bool result = false;
       switch (LOWORD(wparam)) {
         case IDOK:
           finish = true;