Merge branch 'stable-2.15'

* stable-2.15:
  Format all Java files with google-java-format
  Fix support for Velocity and Soy comments
  Use map.computeIfAbsent
  Fix Eclipse warnings about raw types
  Rename parameter to comply with naming convention
  Replace anonymous class with ThreadLocal.withInitial
  Use Logger's built-in formatting
  Move array designators to the type
  Clarify constant declaration
  Replace FluentIterable with Java Stream
  Remove unnecessary import
  Avoid redundant array creation
  Remove redundant specification of type arguments
  Remove redundant semicolons
  Apply google-java-format to all files

Change-Id: If9ba8e41f67e066973d83ac60b6a212cd4432fae