Bug 983770 - fix scrollbars in overflow panel when zoom or edit controls overflow, r=mikedeboer

browser/themes/shared/customizableui/customizeMode.inc.css

@@ -233,7 +233,7 @@ toolbarpaletteitem[place="toolbar"] {
   max-width: 24px;
   min-width: 24px;
   max-height: 24px;
-  height: 24px;
+  min-height: 24px;
   padding: 4px;
 }
 

browser/themes/shared/customizableui/panelUIOverlay.inc.css

@@ -855,11 +855,16 @@ toolbarpaletteitem[place="palette"] > #search-container {
   border-color: hsla(210,4%,10%,0);
   border-bottom-color: hsla(210,4%,10%,.1);
   padding: 0;
-  margin-bottom: -1px;
   transition-property: background-color, border-color;
   transition-duration: 150ms;
 }
 
+/* Make direct siblings overlap borders: */
+.toolbaritem-combined-buttons + .toolbaritem-combined-buttons@inAnyPanel@ {
+  margin-top: -1px;
+  border-top-color: transparent !important;
+}
+
 .toolbaritem-combined-buttons@inAnyPanel@ > toolbarbutton {
   border: 0;
   padding: .5em;