Fix a media server crash (bug 1807910): part one

Add a factory method that creates a Camera object from a remote client

Next:
The changes in authordriver.cpp and android_camera_input.cpp will come.
and the constructor for Camera object will be removed.

include/ui/Camera.h

@@ -78,8 +78,8 @@ class Camera : public BnCameraClient, public IBinder::DeathRecipient
 {
 public:
             // construct a camera client from an existing remote
-            Camera(const sp<ICamera>& camera);
-
+            Camera(const sp<ICamera>& camera);  // to be removed
+    static  sp<Camera>  create(const sp<ICamera>& camera);
     static  sp<Camera>  connect();
                         ~Camera();
             void        init();