Move platform abstraction to base library
Also split v8-core independent methods from checks.h to base/logging.h and
merge v8checks with the rest of checks.
The CPU::FlushICache method is moved to CpuFeatures::FlushICache
RoundUp and related methods are moved to base/macros.h
Remove all layering violations from src/libplatform
BUG=none
R=jkummerow@chromium.org
LOG=n
Review URL: https://codereview.chromium.org/
358363002
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22092
ce2b1a6d-e550-0410-aec6-
3dcde31c8c00