Always keep a transparent scroll stroke to prevent dialog from shifting.

PiperOrigin-RevId: 260179379

Author: phantomesse

angular_components/lib/material_dialog/material_dialog.html

@@ -12,6 +12,7 @@
     <div class="error" [class.expanded]="error != null">{{error}}</div>
 
     <main #main role="presentation"
+          [class.with-scroll-strokes]="shouldShowScrollStrokes"
           [class.top-scroll-stroke]="shouldShowTopScrollStroke"
           [class.bottom-scroll-stroke]="shouldShowBottomScrollStroke">
       <ng-content></ng-content>

angular_components/lib/material_dialog/material_dialog.scss

@@ -87,12 +87,17 @@ main {
   padding: 0 $mat-grid * 3;
   width: 100%;
 
+  &.with-scroll-strokes {
+    border-bottom: 1px transparent solid;
+    border-top: 1px transparent solid;
+  }
+
   &.top-scroll-stroke {
-    border-top: 1px $mat-gray-300 solid;
+    border-top-color: $mat-gray-300;
   }
 
   &.bottom-scroll-stroke {
-    border-bottom: 1px $mat-gray-300 solid;
+    border-bottom-color: $mat-gray-300;
   }
 }