Support the fragment form of Gerrit URLs

Some folks may copy the URL out of their brower location field
rather than using the permalink when creating a Gerrit Depends-On,
so support that as well.

Change-Id: Ie35fde41befcb0c5c062fcc0417afeed1cf60a77

tests/unit/test_gerrit_crd.py

@@ -54,8 +54,11 @@ class TestGerritCRD(ZuulTestCase):
         A.setDependsOn(AM1, 1)
         AM1.setDependsOn(AM2, 1)
 
+        # So that at least one test uses the /#/c/ form of the url,
+        # use it here.
+        url = 'https://%s/#/c/%s' % (B.gerrit.server, B.number)
         A.data['commitMessage'] = '%s\n\nDepends-On: %s\n' % (
-            A.subject, B.data['url'])
+            A.subject, url)
 
         self.fake_gerrit.addEvent(A.addApproval('Approved', 1))
         self.waitUntilSettled()

zuul/driver/gerrit/gerritsource.py

@@ -54,7 +54,10 @@ class GerritSource(BaseSource):
             parsed = urllib.parse.urlparse(url)
         except ValueError:
             return None
-        m = self.change_re.match(parsed.path)
+        path = parsed.path
+        if parsed.fragment:
+            path += '#' + parsed.fragment
+        m = self.change_re.match(path)
         if not m:
             return None
         try: