GitLab

If there exists session sync nodes that use the cache GUID as the ID,
Chrome for Android goes into a deadlock while associating the tabs.

Since SessionModelAssociator::DeleteForeignSession uses its own
syncer::WriteTransaction, we must ensure that we only call that method
without currently holding a syncer::WriteTransaction.

BUG=175782

Review URL: https://chromiumcodereview.appspot.com/12253010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182416 0039d316-1c4b-4281-b951-d872f2087c98