Small cleanup in ProfileCompilationInfo.

Move DeflateBuffer/InflateBuffer to an anonymous namespace
and improve error checking.

Move SafeBuffer definition to the .cc file and make member
functions inline. Add DCHECK()s and change some comparisons
to eliminate potential arithmetic overflow errors.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: I9ca0e8d5c5d8e1393151c48f690cba02f34d4e61
2 files changed