Various GCC 3.6 and clang build fixes.

Remove #error in common_test.h that fires with clang build and replace with
runtime error.
Fix bit rot caused by not compiling with Wthread-safety.
Fix clang build issues in compiler relating to missing header file definitions
in object files.
Other minor build and tidying issues.

Change-Id: Ife829ab0664581936155be524de46e6181c750b0