TODO

Plugin:
- get info about play state, URL etc back from viewer to the plugin
- support all <embed> and <object> attributes that the legacy plugins support
- there still seem to be some unnecessary symbols exported in the plugin .so's

GMP plugin:
- write IDL files (where [_not_ MSDN !] to find documentation?)

Complex plugin:
- write IDL file (nsIHXPlayer.idl available, but incompatible with totem's
  licence exception; is the exception needed for the *plugin* itself?)

NarrowSpace plugin:
- write IDL file (where to find documentation?)