Add support of vrdisplayconnect and vrdisplaydisconnect event

device/vr/android/gvr/gvr_device_provider.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "device/vr/android/gvr/gvr_device_provider.h"
 
 #include "base/android/context_utils.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_utils.h"
 #include "base/android/scoped_java_ref.h"
@@ skipping 40 matching lines @@
         Java_GvrDeviceProvider_getNativeContext(env, j_device_.obj());
 
     if (!gvr_api)
       return;
 
     GvrApiManager::GetInstance()->Initialize(
         reinterpret_cast<gvr_context*>(gvr_api));
   }
 }
 
+void GvrDeviceProvider::SetClient(VRClientDispatcher* client) {
+  if (!vr_device_)
+    return;
+  vr_device_->SetClient(client);
+}
+
 void GvrDeviceProvider::OnGvrApiInitialized(gvr::GvrApi* gvr_api) {
   if (!vr_device_)
     vr_device_.reset(new GvrDevice(this, gvr_api));
 
   // Should fire a vrdisplayconnected event here.
 }
 
 void GvrDeviceProvider::OnGvrApiShutdown() {
   // Nothing to do here just yet. Eventually want to shut down the VRDevice
 }
 
+void GvrDeviceProvider::PollEvents() {
+  if (vr_device_)
+    vr_device_->PollEvents();
+}
+
 }  // namespace device