Analysis tasks page complains about missing repository but with a wrong name

Analysis tasks page complains about missing repository but with a wrong name
https://bugs.webkit.org/show_bug.cgi?id=154468

Reviewed by Chris Dumez.

Fixed the bug by using the right variable in the template literal.

* public/v3/components/customizable-test-group-form.js:
(CustomizableTestGroupForm.prototype._computeRootSetMap): Use querySelector here since Chrome doesn't have
getElementsByClassName on ShadowRoot.
* public/v3/pages/analysis-task-page.js:
(AnalysisTaskPage.prototype._createTestGroupAfterVerifyingRootSetList): Use name which is the name of
repository here.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@196832 268f45cc-cd09-0410-ab3c-d52691b4dbfc