Reviewed by Kevin Decker.

        Convert more code over to C++.
        
        * Plugins/WebBaseNetscapePluginStream.h:
        (WebNetscapePluginStream::plugin):
        (WebNetscapePluginStream::setRequestURL):
        Convert to C++.

        * Plugins/WebBaseNetscapePluginStream.mm:
        (WebNetscapePluginStream::start):
        (WebNetscapePluginStream::stop):
        Ditto.
        
        (WebNetscapePluginStream::startStreamWithResponse):
        Ditto.
        
        (-[WebBaseNetscapePluginStream startStreamWithResponse:]):
        Call the C++ version.
        
        (-[WebBaseNetscapePluginStream impl]):
        New accessor for the C++ class.
        
        * Plugins/WebBaseNetscapePluginView.mm:
        (-[WebBaseNetscapePluginView pluginView:receivedData:]):
        (-[WebBaseNetscapePluginView loadRequest:inTarget:withNotifyData:sendNotification:]):
        (-[WebBaseNetscapePluginView destroyStream:reason:]):
        Call the C++ methods.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@37911 268f45cc-cd09-0410-ab3c-d52691b4dbfc