Reviewed by Dan Bernstein.

        Create a client mach port and pass it to the plug-in host.
        
        * Plugins/Hosted/NetscapePluginHostManager.h:
        * Plugins/Hosted/NetscapePluginHostManager.mm:
        (WebKit::NetscapePluginHostManager::hostForPackage):
        (WebKit::NetscapePluginHostManager::spawnPluginHost):
        * Plugins/Hosted/NetscapePluginHostProxy.h:
        * Plugins/Hosted/NetscapePluginHostProxy.mm:
        (WebKit::NetscapePluginHostProxy::NetscapePluginHostProxy):
        * Plugins/Hosted/WebKitPluginHost.defs:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@38920 268f45cc-cd09-0410-ab3c-d52691b4dbfc