Make platform depend on openmax_dl.
Make platform depend on openmax_dl.

This is required for upcoming openmax_dl changes here:
https://codereview.chromium.org/626183003

but I believe should be done in any case.

BUG=415393

Review URL: https://codereview.chromium.org/635443002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@183311 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