Support LiveEdit on Arm64

BUG=368580
LOG=Y
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/339663007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@21937 ce2b1a6d-e550-0410-aec6-3dcde31c8c00