NXGetArchInfoXXX depends on the OS knowledge of architecture. This CL adds a
custom implementation of those methods to be able to handle newer CPU before
they are handled by the OS. It also add handling for armv7s architecture.
Review URL: https://breakpad.appspot.com/475002
git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1057 4c0a9323-5329-0410-9bdc-e9ce6186880e
