Move StackHandlerConstants to platform-independent frames.h

* src/frames.h: Move StackHandlerConstants here, as it is the same for
  all architectures.

BUG=

Review URL: https://codereview.chromium.org/13638002
Patch from Andy Wingo <wingo@igalia.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14161 ce2b1a6d-e550-0410-aec6-3dcde31c8c00