https://bugs.webkit.org/show_bug.cgi?id=87635

InspectorFileSystemAgent needs weak reference to its frontend to perform
asynchronous operation.

Patch by Taiju Tsuiki <tzik@chromium.org> on 2012-05-29
Reviewed by Yury Semikhatsky.

* inspector/InspectorFileSystemAgent.cpp:
(InspectorFileSystemAgent::FrontendProvider):
(WebCore):
(WebCore::InspectorFileSystemAgent::~InspectorFileSystemAgent):
(WebCore::InspectorFileSystemAgent::enable):
(WebCore::InspectorFileSystemAgent::disable):
(WebCore::InspectorFileSystemAgent::setFrontend):
(WebCore::InspectorFileSystemAgent::clearFrontend):
(WebCore::InspectorFileSystemAgent::restore):
(WebCore::InspectorFileSystemAgent::InspectorFileSystemAgent):
* inspector/InspectorFileSystemAgent.h:
(InspectorFileSystemAgent):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@118783 268f45cc-cd09-0410-ab3c-d52691b4dbfc