Remove WTF_USE_NATIVE_FULLSCREEN_VIDEO as it is no longer used.
Remove WTF_USE_NATIVE_FULLSCREEN_VIDEO as it is no longer used.

Review URL: https://codereview.chromium.org/340443003

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@176353 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