Revert timezone in timestamp

Removes the timezone from the timestamps, as the tooltip shows UTC
offset on mouseover.

Also upgrades most instances of gr-date-formatter to use gr-tooltip.

Bug: Issue 5587
Change-Id: I57c7dcacf0618ffd967eff3cb4ff37a5e1876180

polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.html

@@ -141,7 +141,9 @@ limitations under the License.
     </td>
     <td class="cell updated"
         hidden$="[[isColumnHidden('Updated', visibleChangeTableColumns)]]">
-      <gr-date-formatter date-str="[[change.updated]]"></gr-date-formatter>
+      <gr-date-formatter
+          has-tooltip
+          date-str="[[change.updated]]"></gr-date-formatter>
     </td>
     <td class="cell size u-monospace"
         hidden$="[[isColumnHidden('Size', visibleChangeTableColumns)]]">

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

@@ -99,6 +99,7 @@ limitations under the License.
       <span class="title">Updated</span>
       <span class="value">
         <gr-date-formatter
+            has-tooltip
             date-str="[[change.updated]]"></gr-date-formatter>
       </span>
     </section>

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

@@ -189,7 +189,9 @@ limitations under the License.
           <span class="collapsedContent">[[comment.message]]</span>
         </div>
         <a class="date" href$="[[_computeLinkToComment(comment)]]" on-tap="_handleLinkTap">
-          <gr-date-formatter date-str="[[comment.updated]]"></gr-date-formatter>
+          <gr-date-formatter
+              has-tooltip
+              date-str="[[comment.updated]]"></gr-date-formatter>
         </a>
         <div class="show-hide">
           <label class="show-hide">

polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.html

@@ -37,6 +37,7 @@ limitations under the License.
         <span class="title">Registered</span>
         <span class="value">
           <gr-date-formatter
+              has-tooltip
               date-str="[[_account.registered_on]]"></gr-date-formatter>
         </span>
       </section>

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

@@ -157,8 +157,8 @@ limitations under the License.
               <select
                   is="gr-select"
                   bind-value="{{_localPrefs.time_format}}">
-                <option value="HHMM_12">4:10 PM (PST)</option>
-                <option value="HHMM_24">16:10 (PST)</option>
+                <option value="HHMM_12">4:10 PM</option>
+                <option value="HHMM_24">16:10</option>
               </select>
             </span>
           </section>

polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter.js

@@ -65,10 +65,6 @@
       this._loadPreferences();
     },
 
-    _getTzString: function() {
-      return ' ' + new Date().toString().split(' ').pop();
-    },
-
     _getUtcOffsetString: function() {
       return ' UTC' + moment().format('Z');
     },
@@ -150,7 +146,7 @@
       var now = new Date();
       var format = TimeFormats.MONTH_DAY_YEAR;
       if (this._isWithinDay(now, date)) {
-        return date.format(timeFormat) + this._getTzString();
+        format = timeFormat;
       } else if (this._isWithinHalfYear(now, date)) {
         format = TimeFormats.MONTH_DAY;
       }

polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_test.html

@@ -82,7 +82,6 @@ limitations under the License.
           {time_format: 'HHMM_24', relative_date_in_change_table: false}
         ).then(function() {
           element = fixture('basic');
-          sandbox.stub(element, '_getTzString').returns('');
           sandbox.stub(element, '_getUtcOffsetString').returns('');
           return element._loadPreferences();
         });
@@ -125,7 +124,6 @@ limitations under the License.
           {time_format: 'HHMM_12'}
         ).then(function() {
           element = fixture('basic');
-          sandbox.stub(element, '_getTzString').returns('');
           sandbox.stub(element, '_getUtcOffsetString').returns('');
           return element._loadPreferences();
         });
@@ -144,7 +142,6 @@ limitations under the License.
           {time_format: 'HHMM_12', relative_date_in_change_table: true}
         ).then(function() {
           element = fixture('basic');
-          sandbox.stub(element, '_getTzString').returns('');
           sandbox.stub(element, '_getUtcOffsetString').returns('');
           return element._loadPreferences();
         });
@@ -169,7 +166,6 @@ limitations under the License.
           {time_format: 'HHMM_12', relative_date_in_change_table: true}
         ).then(function() {
           element = fixture('basic');
-          sandbox.stub(element, '_getTzString').returns('');
           return element._loadPreferences();
         });
       });
@@ -184,7 +180,6 @@ limitations under the License.
       setup(function() {
         return stubRestAPI(null).then(function() {
           element = fixture('basic');
-          sandbox.stub(element, '_getTzString').returns('');
           return element._loadPreferences();
         });
       });