Added DataTypeController integration and UI surfacing for syncing Search Engines. Removed some sync fields from search engine proto.

TEST=Ensure that you can enable Search Engine Sync through the about:flags page and sync setup UI. With both enabled search engines should start syncing.
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git-svn-id: svn:// 0039d316-1c4b-4281-b951-d872f2087c98
27 files changed