Merge branch 'stable-2.15' into stable-2.16 * stable-2.15: Automatically format BUILD file with buildifier lint mode Upgrade bazlets to latest stable-2.15 to build with 2.15.9 API Upgrade bazlets to latest stable-2.15 to build with 2.15.8 API Upgrade bazlets to latest stable-2.14 to build with 2.14.18 API Bazel: Include eclipse-out directory in .bazelignore Add explanatory comment to empty BUILD file(s) Change-Id: Id67c34e6bc1b3f6aaa295a338068676e805791d1