Adwaita: combo and menuitem buttons padding fixes

gtk/theme/Adwaita/_common.scss

@@ -774,12 +774,17 @@ $_dot_color: if($variant=='light', $selected_bg_color,
 }
 
 /* menu buttons */
-.menuitem.button.flat {
-  @extend %undecorated_button;
-  outline-offset: -1px;
-  &:hover { background-color: mix($fg_color, $bg_color, 10%); }
-  &:selected { @extend %selected_items; }
-  &:backdrop, &:backdrop:hover {
+.menuitem.button {
+  .label {
+    padding-left: 0;  // label side paddings here need to be reset
+    padding-right: 0; //
+  }
+  &.flat {
+    @extend %undecorated_button;
+    outline-offset: -1px;
+    &:hover { background-color: mix($fg_color, $bg_color, 10%); }
+    &:selected { @extend %selected_items; }
+    &:backdrop, &:backdrop:hover {
     @extend %undecorated_button;
   }
 }
@@ -993,8 +998,8 @@ GtkComboBox {
   &:not(.combobox-entry) .the-button-in-the-combobox {
     padding-top: $padding - 2px;                         // I'd like to avoid this hack, but the button child of combox is actually
     padding-bottom: $padding + $font_compensation - 2px; // 4px bigger than a label.
-    padding-left: 2 * $padding;
-    padding-right: 2 * $padding;
+    padding-left: 2 * $internal_padding;
+    padding-right: 2 * $internal_padding;
   }
 
   -GtkComboBox-arrow-scaling: 0.5;