The eventual goal is for the StatefulBaseRenderer to serve as the
common base class between the DisplayListRenderer and OpenGLRenderer.
This will separate DisplayList recording, Snapshot stack management,
and the GL in OpenGLRenderer.
Additionally, avoid sp<> parameters, and use const parameters in
several places, with the intent of greatly reducing the surface area
where renderer subclasses can modify snapshot stack.
Next steps:
-move bulk of clipping logic into StatefulBaseRenderer
-disable direct snapshot access
Change-Id: Ibc3c6747134ec7daf8ea535866239fa73b874390
This will eventually serve as a base class to allow
DisplayListRenderer to split off from OpenGLRenderer, and could
eventually support other rendering approaches, such as an
SkCanvas/SkPicture.
This will also be the main source of (implementation-independent)
documentation of the canvas/renderer methods.
Change-Id: I52047f338f5cf86a3b0b3002af7154bff5c3c227
