Move footer links and rename them to Old UI/New UI

+ Users don’t know what PolyGerrit is, so this changes makes the
  links more explicit.
+ Placing the Report Bug and Old UI links on the right side avoids
  the anchor popup in Chrome obscuring the text itself.

Bug: Issue 5241
Change-Id: I1eab389cc311df786e21553c1869c4453aa3685d

gerrit-gwtui/src/main/java/com/google/gerrit/client/Gerrit.java

@@ -543,7 +543,7 @@ public class Gerrit implements EntryPoint {
     if (info().gerrit().webUis().contains(UiType.POLYGERRIT)) {
       btmmenu.add(new InlineLabel(" | "));
       Anchor a = new Anchor(
-          C.polyGerrit(), GWT.getHostPageBaseURL() + "?polygerrit=1");
+          C.newUi(), GWT.getHostPageBaseURL() + "?polygerrit=1");
       a.setStyleName("");
       btmmenu.add(a);
     }

gerrit-gwtui/src/main/java/com/google/gerrit/client/GerritConstants.java

@@ -42,6 +42,8 @@ public interface GerritConstants extends Constants {
   String branchDeletionDialogTitle();
   String branchDeletionConfirmationMessage();
 
+  String newUi();
+
   String notSignedInTitle();
   String notSignedInBody();
 
@@ -130,6 +132,4 @@ public interface GerritConstants extends Constants {
 
   String searchDropdownChanges();
   String searchDropdownDoc();
-
-  String polyGerrit();
 }

gerrit-gwtui/src/main/java/com/google/gerrit/client/GerritConstants.properties

@@ -23,6 +23,8 @@ branchCreationConfirmationMessage = The following branch was successfully create
 branchDeletionDialogTitle = Branch Deletion
 branchDeletionConfirmationMessage = Do you really want to delete the following branches?
 
+newUi = New UI
+
 notSignedInTitle = Code Review - Session Expired
 notSignedInBody = <b>Session Expired</b>\
 <p>You are no longer signed in to Gerrit Code Review.</p>\
@@ -113,5 +115,3 @@ stringListPanelDown = Down
 
 searchDropdownChanges = Changes
 searchDropdownDoc = Docs
-
-polyGerrit = PolyGerrit

polygerrit-ui/app/elements/gr-app.html

@@ -54,6 +54,8 @@ limitations under the License.
       }
       footer {
         background-color: var(--footer-background-color, #eee);
+        display: flex;
+        justify-content: space-between;
         padding: .5rem var(--default-horizontal-margin);
       }
       main {
@@ -128,17 +130,20 @@ limitations under the License.
       </div>
     </main>
     <footer role="contentinfo">
+      <div>
         Powered by <a href="https://www.gerritcodereview.com/" rel="noopener"
         target="_blank">Gerrit Code Review</a>
         ([[_version]])
-      |
+      </div>
+      <div>
         <a class="feedback"
             href="https://bugs.chromium.org/p/gerrit/issues/entry?template=PolyGerrit%20Issue"
-          rel="noopener" target="_blank">Report PolyGerrit Bug</a>
+            rel="noopener" target="_blank">Report bug</a>
         <template is="dom-if" if="[[_computeShowGwtUiLink(_serverConfig)]]">
           |
-        <a id="gwtLink" href$="/?polygerrit=0#[[_path]]" rel="external">GWT UI</a>
+          <a id="gwtLink" href$="/?polygerrit=0#[[_path]]" rel="external">Old UI</a>
         </template>
+      </div>
     </footer>
     <gr-overlay id="keyboardShortcuts" with-backdrop>
       <gr-keyboard-shortcuts-dialog