clang-format/java: Break after annotations on fields in Chromium style.

Chromium follows the Android style guide for Java code, and that doesn't make
the distinction between fields and non-fields that the Google Java style guide
makes:

https://source.android.com/source/code-style.html#use-standard-java-annotations
https://google.github.io/styleguide/javaguide.html#s4.8.5-annotations

llvm-svn: 250422