Android 5.1 去掉首次进入沉浸模式的提示

首次进入沉浸模式会有一个如图的提示：

<string name="immersive_mode_confirmation" msgid="7227416894979047467">"从顶部向下滑动即可退出全屏模式。"string>

源码位置：
布局：

frameworks/base/core/res/res/layout/immersive_mode_cling.xml

代码：

frameworks/base/policy/src/com/android/internal/policy/impl/ImmersiveModeConfirmation.java

屏蔽提示方法：

--- a/frameworks/base/policy/src/com/android/internal/policy/impl/ImmersiveModeConfirmation.java
+++ b/frameworks/base/policy/src/com/android/internal/policy/impl/ImmersiveModeConfirmation.java
@@ -333,13 +333,13 @@ public class ImmersiveModeConfirmation {
         public void handleMessage(Message msg) {
             switch(msg.what) {
                 case SHOW:
-                    handleShow();
+                    // handleShow();
                     break;
                 case HIDE:
                     handleHide();
                     break;
                 case PANIC:
-                    handlePanic();
+                    // handlePanic();
                     break;
             }
         }