Implement WebVR presentation pausing for VR Shell Menu Mode

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 8a3637d25902a91e6e08143cae45ada582d26a32..b206baf6f56831cdae16dce84136c04ad65a0bf8 100644
--- a/device/vr/android/gvr/gvr_device_provider.cc
+++ b/device/vr/android/gvr/gvr_device_provider.cc
@@ -56,6 +56,7 @@ void GvrDeviceProvider::Initialize() {
 }
 
 bool GvrDeviceProvider::RequestPresent() {
+  DCHECK(main_thread_task_runner_->BelongsToCurrentThread());
   device::GvrDelegateProvider* delegate_provider =
       device::GvrDelegateProvider::GetInstance();
   if (!delegate_provider)
@@ -86,9 +87,8 @@ void GvrDeviceProvider::ExitPresent() {
 
 void GvrDeviceProvider::OnGvrDelegateReady(GvrDelegate* delegate) {
   main_thread_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&GvrDeviceProvider::GvrDelegateReady, base::Unretained(this),
-                 base::Unretained(delegate)));
+      FROM_HERE, base::Bind(&GvrDeviceProvider::GvrDelegateReady, this,
+                            base::Unretained(delegate)));
 }
 
 void GvrDeviceProvider::OnGvrDelegateRemoved() {
@@ -98,6 +98,28 @@ void GvrDeviceProvider::OnGvrDelegateRemoved() {
   ExitPresent();
 }
 
+void GvrDeviceProvider::OnDisplayBlur() {
+  if (!main_thread_task_runner_->BelongsToCurrentThread()) {
+    main_thread_task_runner_->PostTask(
+        FROM_HERE, base::Bind(&GvrDeviceProvider::OnDisplayBlur, this));
+    return;
+  }
+  if (!vr_device_)
+    return;
+  vr_device_->OnDisplayBlur();
+}
+
+void GvrDeviceProvider::OnDisplayFocus() {
+  if (!main_thread_task_runner_->BelongsToCurrentThread()) {
+    main_thread_task_runner_->PostTask(
+        FROM_HERE, base::Bind(&GvrDeviceProvider::OnDisplayFocus, this));
+    return;
+  }
+  if (!vr_device_)
+    return;
+  vr_device_->OnDisplayFocus();
+}
+
 void GvrDeviceProvider::GvrDelegateReady(GvrDelegate* delegate) {
   DCHECK(main_thread_task_runner_->BelongsToCurrentThread());