module to contain only code necessary for testing the compiler
optimizations and diagnostics. This commit comprises the following changes:
1. Rename the OSLogPrototype module to OSLogTestHelper and rename the files.
2. Make the private module: OSLogTestHelper independent of os overlay.
3. Simplify the os log test suites and make them not perform logging.
4. Enable the os log test suites on all platforms.
<rdar://problem/60542172>
