Reviewed by Darin.

    Reviewed by Darin.

	Fixed: <rdar://problem/4038529> Infinite progress bar loading webcams and other sites that use multipart/x-mixed-replace

	The previous patch I landed prevented us from loading multipart/x-mixed-replace but did not always update the progress bar accordingly.
        This stops websites from having seemingly infinite progress in the browser UI.

        * WebCoreSupport.subproj/WebSubresourceClient.m:
        (-[WebSubresourceClient didReceiveResponse:]): If this is "multipart/x-mixed-replace", remove the WebBaseResourceHandleDelegate client from
        the datasource's subresource array, otherwise -[WebDataSource isLoading] incorrectly returns YES.   Also it's possible at this point in
         time we're done loading now (loaded everything else except for the multipart/x-mixed-replace content) so go ahead and check to see if
         in fact we're complete.
        * WebView.subproj/WebMainResourceClient.m:
        (-[WebMainResourceClient connection:didReceiveResponse:]): ditto

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@8800 268f45cc-cd09-0410-ab3c-d52691b4dbfc