Notify VRDeviceProviders when there are pages listening for vrdisplayactivate

device/vr/android/gvr/gvr_device_provider.cc

Index: device/vr/android/gvr/gvr_device_provider.cc
diff --git a/device/vr/android/gvr/gvr_device_provider.cc b/device/vr/android/gvr/gvr_device_provider.cc
index 31a28f3b4914d7fc25c6dae7c949d8a0467454c3..5101ba9a8f265ad8e735618337e1322c0512c840 100644
--- a/device/vr/android/gvr/gvr_device_provider.cc
+++ b/device/vr/android/gvr/gvr_device_provider.cc
@@ -119,4 +119,13 @@ void GvrDeviceProvider::SwitchToNonPresentingDelegate() {
       GAMEPAD_SOURCE_GVR);
 }
 
+void GvrDeviceProvider::SetListeningForActivate(bool listening) {
+  device::GvrDelegateProvider* delegate_provider =
+      device::GvrDelegateProvider::GetInstance();
+  if (!delegate_provider)
+    return;
+
+  delegate_provider->SetListeningForActivate(listening);
+}
+
 }  // namespace device