Bug: 17208461
There's a potential race condition between HardwareRenderer.destroy()
being called (which calls destroyCanvasAndSurface()) and the renderer
being finalized (which is what calls freePrefetchedLayers), during which
time it's possible we get a TRIM_MEMORY_COMPLETE and destroy the EGL
context.
Fix this race condition by moving stopDrawing() and freePrefetchedLayers()
into destroyCanvasAndSurface() where they should have been in the first
place.
Also, if we hit the assertion failure, dump the current state of
Caches to try and provide more context for the failure.
Change-Id: Ife0ba3562041e8b08e87e3e13640472b3004eed6
17035b0211