Fix layout of change overflow action menu on mobile

Bug: Issue 5351
Change-Id: I2874c00123f9b51b79dc34cc43f0292f545e9ec9

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

@@ -52,10 +52,12 @@ limitations under the License.
       @media screen and (max-width: 50em) {
         :host,
         section,
-        gr-button {
+        gr-button,
+        gr-dropdown {
           display: block;
         }
-        gr-button {
+        gr-button,
+        gr-dropdown {
           margin-bottom: .5em;
           margin-left: 0;
         }
@@ -69,7 +71,7 @@ limitations under the License.
         id="moreActions"
         down-arrow
         vertical-offset="32"
-        horizontal-align="right"
+        horizontal-align="left"
         on-tap-item-abandon="_handleAbandonTap"
         on-tap-item-cherrypick="_handleCherrypickTap"
         on-tap-item-delete="_handleDeleteTap"

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

@@ -27,6 +27,7 @@ limitations under the License.
       }
       .dropdown-trigger {
         text-decoration: none;
+        width: 100%;
       }
       .dropdown-content {
         background-color: #fff;