Reduce number of unique paths used when drawing the battery icon.

By clipping the canvas instead of the path we can avoid both the
computation of the new path on the UI Thread and get cache reuse
of the existing path on the RenderThread.

Bug: 64487466
Test: SystemUiJankTests#testNotificationListPull
Change-Id: Ic237aa1bc6b50b452eb9c71e23748b5d454dfa3c
1 file changed