- Add some logging to nsObjectLoadingContent
- Add a StopPlugin() method to nsIObjectFrame
- Make use of that in PrepareInstanceOwner, so that loading a new plugin in
the same frame works as expected
- Initialize <applet> and <embed> elements to eType_Loading, so that the type is
only eType_Plugin if mURI and mContentType are valid
r+sr=bz
git-svn-id: svn://10.0.0.236/trunk@183271 18797224-902f-48f8-a5cc-f745e15eee43