Sends NetworkChangeNotifier connection type changes to Blink, to support NetInfo v3.

Design doc: https://docs.google.com/a/chromium.org/document/d/1LTk9uVMGi4kurzcF5ellsAJReTF31fFJMHrQwSVtBjc/

BUG=368358

Review URL: https://codereview.chromium.org/298803006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@273555 0039d316-1c4b-4281-b951-d872f2087c98
14 files changed