Add heap configuration for 1080p phones with 2048m

 * Increase heap start size to 16m to minimize GC with larger bitmaps

Change-Id: I8fbba2e5a2a2cf2d7a6898ca6bae8639d6cf5a19
hwui: Update configuration for 2GB/1080p devices

Change-Id: I73357a35bee22d76d3fe8a98ece91c5c9d19371d
Update HWUI config for xxhdpi/2GB devices

Change-Id: Ic9ba16b0360f2b755a1d23aa51eddc61beee2bac