fix(dropdown): multiple search button padding and wrapping

This PR fixes

multiple search button dropdown had wrong padding
Placeholders in multiple search dropdowns were wrapping
Search in dropdown buttons had ghosting text

src/definitions/modules/dropdown.less

@@ -681,6 +681,9 @@ select.ui.dropdown {
     color: @selectionTextUnderlayColor !important;
   }
 
+  .ui.search.dropdown.button > span.sizer {
+    display: none;
+  }
 
   /* Search Menu */
   .ui.search.dropdown .menu {
@@ -742,7 +745,7 @@ select.ui.dropdown {
   ---------------*/
 
   /* Multiple Selection */
-  .ui.multiple.dropdown {
+  .ui.ui.multiple.dropdown {
     padding: @multipleSelectionPadding;
   }
   .ui.multiple.dropdown .menu {
@@ -772,6 +775,11 @@ select.ui.dropdown {
     max-width: 100%;
     margin: @multipleSelectionChildMargin;
     line-height: @multipleSelectionChildLineHeight;
+    &.default {
+      white-space: nowrap;
+      overflow: hidden;
+      text-overflow: ellipsis;
+    }
   }
   .ui.multiple.dropdown > .label ~ input.search {
     margin-left: @multipleSelectionSearchAfterLabelDistance !important;
@@ -825,6 +833,10 @@ select.ui.dropdown {
       width: @multipleSelectionSearchStartWidth;
       line-height: @multipleSelectionChildLineHeight;
     }
+
+    .ui.multiple.search.dropdown.button {
+      min-width: @selectionMinWidth;
+    }
   }
 }