Add checking for license formats to third_party/PRESUBMIT

Since we expect a certain format for the "License:" field, it's better to
check it earlier -- during the presubmit stage, so people won't get
surprises later.

Also, updated the license checking code to accept multiple licenses if
one of them is compatible with Android.

BUG=168324
R=dannyb@google.com, mkosiba@chromium.org
TBR=darin@chromium.org

Review URL: https://codereview.chromium.org/146803006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250068 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250068