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This upstreams all of Chrome for Android's cast code with the exception of:
1. The YouTube support code.
2. The id of the Chrome cast receiver.

The YouTube support code and the id of Chrome cast receiver have to remain
proprietory due to licencing restrictions. The tests will be upstreamed
seperately, but need further work to make them independent of other
downstream code.

BUG=315088

Review URL: https://codereview.chromium.org/928643003

Cr-Commit-Position: refs/heads/master@{#322569}