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 c484376ca86eb1d750eda5fed87c9455af288da6..702694a3485fadac28b31a5e13a1adc042de0dbe 100644
--- a/device/vr/android/gvr/gvr_device_provider.cc
+++ b/device/vr/android/gvr/gvr_device_provider.cc
@@ -117,4 +117,13 @@ 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