Display and wfd synchronization during teardown

* Provide a binder interface call for wfd module
to inform display about the start/stop/pause/resume
of wfd session.

* This is needed for wfd-hdmi synchronization in
case of v4l2 wfd solution. If hdmi is plugged
in during v4l2 wfd session, display-hal waits in
uevent thread for wfd teardown notification from
wfd module, before going ahead with configuring
external display.

* For VDS WFD solution, display-hal waits in uevent
thread for wfd-teardown to be signalled from
the composition thread.

Change-Id: I9514cb5bc7ff81de0b5dd4cdf66d8286a64ba094
diff --git a/libhwcomposer/hwc_virtual.h b/libhwcomposer/hwc_virtual.h
index 6bc3898..87004c3 100644
--- a/libhwcomposer/hwc_virtual.h
+++ b/libhwcomposer/hwc_virtual.h
@@ -33,7 +33,7 @@
     explicit HWCVirtualBase(){};
     virtual ~HWCVirtualBase(){};
     // instantiates and returns the pointer to VDS or V4L2 object.
-    static HWCVirtualBase* getObject();
+    static HWCVirtualBase* getObject(bool isVDSEnabled);
     virtual int prepare(hwc_composer_device_1 *dev,
                           hwc_display_contents_1_t* list) = 0;
     virtual int set(hwc_context_t *ctx, hwc_display_contents_1_t *list) = 0;