[EFL] Use mutex locker in wakeUp() to ensure thread-safety.

[EFL] Use mutex locker in wakeUp() to ensure thread-safety.
https://bugs.webkit.org/show_bug.cgi?id=101132

Patch by Byungwoo Lee <bw80.lee@samsung.com> on 2012-11-28
Reviewed by Gyuyoung Kim.

Add mutex locker for the ecore pipe to ensure thread-safety of
RunLoop::wakeUp().

RunLoop::wakeUp() can be called by multiple thread. It uses
ecore_pipe_write() function but the function is not thread-safe.

* platform/RunLoop.h:
(RunLoop):
* platform/efl/RunLoopEfl.cpp:
(WebCore::RunLoop::wakeUp):

Change-Id: I36bae620af903781cdb3470888aabc434dbdb7b9
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@136006 268f45cc-cd09-0410-ab3c-d52691b4dbfc