Fix NPE in ActivityView on surface destruction

Instance variable mSurface in ActivityView was not updated after surface
destroy/create cycle, which lead to NPE when we were trying to release
it again after second destroy callback.

Bug: 63338670
Test: Create app with activityView, cause activity restart.
Change-Id: I96447ebe77d175050565641ba94b748d2b633d99
1 file changed