Merge "Fill in javadocs for translation feature." into sc-dev am: 1553fc7f...

Merge "Fill in javadocs for translation feature." into sc-dev am: 1553fc7f am: 4b02f452 am: db0fbc2f am: 0943b1df

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15597859

Change-Id: I8811e70a0b9b64cb89f5077ed79487df5787f7c5