clang-format: Keep more trailing annotations on the same line.

More precisely keep all short annotations (<10 characters) on the same
line if possible. Previously, clang-format would only prefer to do so
for "const", "override" and "final". However, it seems to be generally
preferable, especially because some codebases have to wrap those in
macros for backwards compatibility.

Before:
  void someLongFunction(int someLongParameter)
      OVERRIDE {}

After:
  void someLongFunction(
      int someLongParameter) OVERRIDE {}

This fixes llvm.org/PR19363.