fix(aot): Toolbar styles (#2252)

Rounded corners on the first and last buttons. Size of the hangup button
on hover.

css/_toolbars.scss

         /**
          * Toolbar button styles for always on top.
          */
-        > .button {
+        .button {
             font-size: $alwaysOnTopToolbarFontSize;
             height: $alwaysOnTopToolbarSize;
             line-height: $alwaysOnTopToolbarSize;
             width: $alwaysOnTopToolbarSize;
+            &_hangup, &_hangup:hover {
+                font-size: $alwaysOnTopToolbarFontSize;
+            }
         }
     }
 

react/features/toolbox/components/StatelessToolbarButton.js

         const attributes = getButtonAttributesByProps(button);
 
         return (
-            <a
-                { ...attributes }
-                onClick = { this._onClick }>
-                { this.props.children }
-            </a>
+            <div className = { `toolbar-button-wrapper ${button.id}-wrapper` }>
+                <a
+                    { ...attributes }
+                    onClick = { this._onClick }>
+                    { this.props.children }
+                </a>
+            </div>
         );
     }
 

react/features/toolbox/components/ToolbarButton.web.js

             );
         }
 
-        return (
-            <div className = { `toolbar-button-wrapper ${button.id}-wrapper` }>
-                { children }
-            </div>
-        );
+        return children;
     }
 
     /**