Make a field final.

Make a field that can be final, final.

Change-Id: I597ef43bad5045a63e7e9fe6eedd8e0f0a637ca4
Merge "Make a field final."
Clean up test makefiles.

The build system takes care of linking the correct STL and gtest
libraries for you, and specifying them manually confuses the build
system when using libc++.

Change-Id: I9f76ab26a63ace51293614cfb5ca002f37438e02
Merge "Clean up test makefiles."
Clean up makefile cruft.

The build system already takes care of all these things.

Change-Id: Idef80b554e07cef5e5ed2adf1b5740a76f13ef6d
Merge "Clean up makefile cruft."