Bug 1528206 - Clean up browser/themes/windows/customizableui/panelUI.css. r=dao

Differential Revision: https://phabricator.services.mozilla.com/D19935

--HG--
extra : moz-landing-system : lando

browser/themes/windows/customizableui/panelUI.css

@@ -21,10 +21,16 @@
   background: var(--arrowpanel-background);
   color: var(--arrowpanel-color);
   border: 1px solid var(--arrowpanel-border-color);
-  border-radius: 3.5px;
   margin-top: -4px;
 }
 
+/* Add border-radius on Windows 7 */
+@media (-moz-os-version: windows-win7) {
+  #BMB_bookmarksPopup menupopup[placespopup=true] > hbox {
+    border-radius: 3.5px;
+  }
+}
+
 /* Add some space at the top because there are no headers: */
 #BMB_bookmarksPopup menupopup[placespopup=true] > hbox > .popup-internal-box > .arrowscrollbox-scrollbox  {
   padding-top: 4px;
@@ -43,17 +49,6 @@ menuitem.subviewbutton[disabled]:not(.menuitem-iconic) {
   min-height: 22px;
 }
 
-/* Win8 and beyond. */
-@media not (-moz-os-version: windows-win7) {
-  #BMB_bookmarksPopup menupopup[placespopup=true] > hbox,
-  #edit-controls@inAnyPanel@,
-  #zoom-controls@inAnyPanel@,
-  #edit-controls@inAnyPanel@ > toolbarbutton,
-  #zoom-controls@inAnyPanel@ > toolbarbutton {
-    border-radius: 0;
-  }
-}
-
 /* Anchor the bookmark menu drop down panel at the same height as other
    panels when in the #toolbar-menubar */
 #toolbar-menubar #BMB_bookmarksPopup {