Tweak some RenderNode API surfaces

* no-arg #start()
* remove no-op #destroy method
* fix a Java-imposed quirk that you can't draw a
  currently invalid RenderNode, forcing bottom-up
  recording for no particular reason

Test: builds
Change-Id: I28b41c83b4f7f9ddced843b0d57e9ac510d40ae5
7 files changed