The google-objc-avoid-throwing-exception check enforces the Google
Objective-C Style Guide's prohibition on throwing exceptions in user
code but the check incorrectly triggers findings for code emitted from
system headers. This commit suppresses any findings that do not have
valid locations or are emitted from macros in system headers.
Avoid Throwing Exceptions, Google Objective-C Style Guide:
Ran clang-tidy lit tests.