This disables the perf support in Android because of build problems with librt (should be fixable with a bit of effort, but priority is low).

BUG=
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/360783006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22146 ce2b1a6d-e550-0410-aec6-3dcde31c8c00