Creating PinnedStackController.

- Creating a PinnedStackController to keep track of the state of the PIP
  to prevent changes in the system (ie. IME showing) and user interaction
  from clobbering each other.
- Refactoring calls in AM into WM/controller

Test: android.server.cts.ActivityManagerPinnedStackTests

Change-Id: Ie59dfd45d5c54764ba69a589b3b8148845e92cc3
Signed-off-by: Winson Chung <winsonc@google.com>
diff --git a/bridge/src/android/view/IWindowManagerImpl.java b/bridge/src/android/view/IWindowManagerImpl.java
index db5b119..9ec546e 100644
--- a/bridge/src/android/view/IWindowManagerImpl.java
+++ b/bridge/src/android/view/IWindowManagerImpl.java
@@ -591,6 +591,20 @@
     }
 
     @Override
+    public void registerPinnedStackListener(int displayId, IPinnedStackListener listener) throws RemoteException {
+    }
+
+    @Override
+    public Rect getPictureInPictureDefaultBounds(int displayId) {
+        return null;
+    }
+
+    @Override
+    public Rect getPictureInPictureMovementBounds(int displayId)  {
+        return null;
+    }
+
+    @Override
     public void setResizeDimLayer(boolean visible, int targetStackId, float alpha)
             throws RemoteException {
     }