Frameworks/base: Replace LOG_FATAL_IF in core/jni

Do not use LOG_FATAL_IF in JNI setup. This is one-time on startup
and important enough to always check.

Add a header with common helper definitions. Move to inlined functions
instead of macros to clean up the code.

Change-Id: Ib12d0eed61b110c45d748e80ec36c563e9dec7e5