More Clutter API
This is a bunch of API additions derived from making MetaShapedTexture a ClutterContent implementation. I'm splitting this out to ease review burden and allow us to move towards ClutterContent in small, well defined and sane steps.
Three additions were made:
clutter_content_invalidate_size(): necessary for when a ClutterActor has
CLUTTER_REQUEST_CONTENT_SIZErequest mode, and the ClutterContent changed its preferred size. Currently, there is no way to notify these actors about size changes.
clutter_paint_node_add_multitexture_rectangle(): this is necessary for wrapping
cogl_framebuffer_draw_multitextured_rectangle()calls. They are not equivalent to multiple calls to
cogl_framebuffer_draw_textured_rectangle()-- the former uses different layers of the pipeline, the latter uses only the first layer.
ClutterRootNode: it is a paint node that is the top-most node on a paint node tree.