Remove duplicated rule from core.gyp. This rule is covered by config.gyp.
Remove duplicated rule from core.gyp. This rule is covered by config.gyp.

Review URL: https://codereview.chromium.org/60633007

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@161420 bbb929c8-8fbe-4397-9dbb-9b2b20218538

primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs