More support for DYLIB_INSTALL_NAME_BASE
More support for DYLIB_INSTALL_NAME_BASE

BUG=http://crbug.com/90199
TEST=make-built chrome can play youtube

Review URL: http://codereview.chromium.org/7696014/


witwall/gyp,witwall/gyp,witwall/gyp,witwall/gyp,witwall/gyp