<http://webkit.org/b/51889> WebFrameLoaderClient::createMediaPlayerProxyPlugin() should use WebCore::PluginInfo.name

Reviewed by Eric Carlson.

This originally broke in r61581.  It is inside an
ENABLE(PLUGIN_PROXY_FOR_VIDEO) macro, so it didn't break the Mac
build then.

* WebCoreSupport/WebFrameLoaderClient.mm: Call
(WebFrameLoaderClient::createMediaPlayerProxyPlugin): Updated to
use WebCore::PluginInfo.name instead of
-[WebBasePluginPackage name].

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@74996 268f45cc-cd09-0410-ab3c-d52691b4dbfc