Roll Brotli dfc5a9f2151a -> 7f848593bd2e

This brings in latest Brotli compression format change.

7f848593bd2e Enable the static dictionary in the Brotli decoder.
2733d6c0c2d6 Add the initial version of the static dictionary and transforms to Brotli.
cbd5cb55f487 Updates to Brotli compression format, decoder and encoder

BUG=
TEST=compiled

Review URL: https://codereview.chromium.org/189403008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255597 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255598 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255598