Merge "Add a no recent tasks message to the keyboard quick switch view" into udc-dev

quickstep/src/com/android/launcher3/taskbar/KeyboardQuickSwitchController.java

@@ -129,8 +129,8 @@ public final class KeyboardQuickSwitchController implements
      */
     int launchFocusedTask() {
         // Return -1 so that the RecentsView is not incorrectly opened when the user closes the
-        // quick switch view by tapping the screen.
-        return mQuickSwitchViewController == null
+        // quick switch view by tapping the screen or when there are no recent tasks.
+        return mQuickSwitchViewController == null || mTasks.isEmpty()
                 ? -1 : mQuickSwitchViewController.launchFocusedTask();
     }