[GM3Restyling] Update soft dropdown combobox styles

Bug: 368246828
Change-Id: Ib386951c95cc0f7adf5922b2b483a06d364e6328
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/5966475
Reviewed-by: Kim-Anh Tran <[email protected]>
Commit-Queue: Kim-Anh Tran <[email protected]>
Auto-Submit: Kateryna Prokopenko <[email protected]>

Author: Kateryna Prokopenko

front_end/ui/legacy/softDropDownButton.css

@@ -12,14 +12,18 @@ button.soft-dropdown {
   background: none;
   max-width: 120px;
 
-  devtools-icon {
-    top: 1px;
+  &[disabled] {
+    background: var(--sys-color-state-disabled-container);
+    color: var(--sys-color-state-disabled);
+
+    devtools-icon {
+      color: var(--sys-color-state-disabled);
+    }
   }
-}
 
-button.soft-dropdown[disabled] {
-  background: var(--sys-color-state-disabled-container);
-  color: var(--sys-color-state-disabled);
+  devtools-icon {
+    top: var(--sys-size-2);
+  }
 }
 
 button.soft-dropdown > .title {