Camera2: fix onClosed callback issue

The camera isClosed status shouldn't be checked to fire onClosed callback,
otherwise, onClosed callback is almost never fired when camera close is called
because the camera device is already closed.

Change-Id: I987242d53a12082828a992404ed55ee8a378f93f
diff --git a/core/java/android/hardware/camera2/impl/CameraDevice.java b/core/java/android/hardware/camera2/impl/CameraDevice.java
index 5ec01ad..2c8a5c2 100644
--- a/core/java/android/hardware/camera2/impl/CameraDevice.java
+++ b/core/java/android/hardware/camera2/impl/CameraDevice.java
@@ -106,9 +106,7 @@
 
     private final Runnable mCallOnClosed = new Runnable() {
         public void run() {
-            if (!CameraDevice.this.isClosed()) {
-                mDeviceListener.onClosed(CameraDevice.this);
-            }
+            mDeviceListener.onClosed(CameraDevice.this);
         }
     };