Open notifications by a mouse click on status bar.

Bug: 22304981
Change-Id: I471e2ca27532a2e788b0fcabf9a402dedd09a5c0

packages/SystemUI/src/com/android/systemui/statusbar/phone/PanelView.java

@@ -222,6 +222,15 @@ public abstract class PanelView extends FrameLayout {
             return false;
         }
 
+        // On expanding, single mouse click expands the panel instead of dragging.
+        if (isFullyCollapsed() && event.getPointerCount() == 1
+                && event.getToolType(0) == MotionEvent.TOOL_TYPE_MOUSE) {
+            if (event.getAction() == MotionEvent.ACTION_UP) {
+                expand(true);
+            }
+            return true;
+        }
+
         /*
          * We capture touch events here and update the expand height here in case according to
          * the users fingers. This also handles multi-touch.