Fix the variable expansion prefix for copy_asan_dylib_path in the direct dependent settings.
According to https://code.google.com/p/gyp/wiki/InputFormatReference#Processing_Order,
in order for the path variable to be expanded in the context of the dependent target dictionary,
it should have the '>' prefix.

BUG=228243
R=mark@chromium.org

Review URL: https://codereview.chromium.org/18903002

git-svn-id: http://src.chromium.org/chrome/trunk/src/testing@210562 4ff67af0-8c30-449e-8e8b-ad334ec8d88c