Revert "Don't use C++ features when building test code as C."

This reverts commit 6d93d57ab03f4c13dca65921cadc6f1e6d244cff.
Revert "Fix when is 'self' used as a parameter name in Python"

This reverts commit a6efdb7999298de6be8c5b4f1fca4ff60ac1fb20.