DOCUMENTATION ONLY: try to clarify gravity vs layout_gravity
DOCUMENTATION ONLY: try to clarify gravity vs layout_gravity

Based on 3rd party developer observation, this is a source of much
confusion and layout mistakes.

Change-Id: I2cb6ae1540fe2444582403d9100478ebe02df985

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base