[content shell] Use the TestRunner library again and remove the mock testRunner

BUG=111316,173079
TEST=content_browsertests still work, almost all layout tests pass
[email protected]


Review URL: https://chromiumcodereview.appspot.com/12258047

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182794 0039d316-1c4b-4281-b951-d872f2087c98
11 files changed