Merge "Fall back to the source module for variants that the corresponding...
Merge "Fall back to the source module for variants that the corresponding prebuilt doesn't define." am: 1b2bae1b am: 45f0028d am: b9243e92 am: a6aafdb9
Change-Id: I12beeae5a256ef9b63a11eb70c32aab1705c2c50