Use OwnPtr<PluginControllerProxy> for storing plug-in controllers in WebProcessConnection
https://bugs.webkit.org/show_bug.cgi?id=115259

Reviewed by Andreas Kling.

* PluginProcess/WebProcessConnection.cpp:
(WebKit::WebProcessConnection::addPluginControllerProxy):
(WebKit::WebProcessConnection::removePluginControllerProxy):
(WebKit::WebProcessConnection::didClose):
* PluginProcess/WebProcessConnection.h:
(WebProcessConnection):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149259 268f45cc-cd09-0410-ab3c-d52691b4dbfc