Add haptic feedback when All Apps button is pressed

Bug 5432097

Change-Id: I600054705b7c48a69ee17bb4058c91ea8cf7260d
diff --git a/src/com/android/launcher2/Launcher.java b/src/com/android/launcher2/Launcher.java
index 5eaf773..6727a42 100644
--- a/src/com/android/launcher2/Launcher.java
+++ b/src/com/android/launcher2/Launcher.java
@@ -1679,7 +1679,7 @@
             if (mState == State.APPS_CUSTOMIZE) {
                 showWorkspace(true);
             } else {
-                showAllApps(true);
+                onClickAllAppsButton(v);
             }
         }
     }
@@ -1722,6 +1722,8 @@
      * @param v The view that was clicked.
      */
     public void onClickAllAppsButton(View v) {
+        // Provide the same haptic feedback that the system offers for virtual keys.
+        v.performHapticFeedback(HapticFeedbackConstants.VIRTUAL_KEY);
         showAllApps(true);
     }