Add support of vrdisplayconnect and vrdisplaydisconnect event

device/vr/vr_device_manager.cc

Index: device/vr/vr_device_manager.cc
diff --git a/device/vr/vr_device_manager.cc b/device/vr/vr_device_manager.cc
index b774ad248b762c7018e36f3040eded2d48ba6e7d..d45a4a10ca81dea68061693ee78bee5159574a42 100644
--- a/device/vr/vr_device_manager.cc
+++ b/device/vr/vr_device_manager.cc
@@ -127,6 +127,23 @@ void VRDeviceManager::OnDeviceChanged(VRDisplayPtr device) {
     service->client()->OnDisplayChanged(device.Clone());
 }
 
+void VRDeviceManager::OnDeviceConnectionStatusChanged(VRDevice* device,
+                                                      bool isConnected) {
+  if (isConnected) {
+    VRDisplayPtr vr_device_info = device->GetVRDevice();
+    if (vr_device_info.is_null())
+      return;
+
+    vr_device_info->index = device->id();
+
+    for (const auto& service : services_)
+      service->client()->OnDisplayConnected(vr_device_info.Clone());
+  } else {
+    for (const auto& service : services_)
+      service->client()->OnDisplayDisconnected(device->id());
+  }
+}
+
 void VRDeviceManager::InitializeProviders() {
   if (vr_initialized_) {
     return;
@@ -155,7 +172,7 @@ void VRDeviceManager::SchedulePollEvents() {
 
 void VRDeviceManager::PollEvents() {
   for (const auto& provider : providers_)
-    provider->PollEvents();
+    provider->PollEvents(this);
 }
 
 void VRDeviceManager::StopSchedulingPollEvents() {