Fixes WebVR presentation from within VRShell.

chrome/browser/android/vr_shell/vr_shell.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 "chrome/browser/android/vr_shell/vr_shell.h"
 
 #include <android/native_window_jni.h>
 
 #include <string>
 #include <utility>
@@ skipping 353 matching lines @@
 }
 
 void VrShell::CreateVRDisplayInfo(
     const base::Callback<void(device::mojom::VRDisplayInfoPtr)>& callback,
     uint32_t device_id) {
   PostToGlThreadWhenReady(base::Bind(&VrShellGl::CreateVRDisplayInfo,
                                      gl_thread_->GetVrShellGl(), callback,
                                      device_id));
 }
 
+void VrShell::SetSubmitClient(
+    device::mojom::VRSubmitFrameClientPtr submit_client) {
+  PostToGlThreadWhenReady(
+      base::Bind(&VrShellGl::SetSubmitClient, gl_thread_->GetVrShellGl(),
+                 base::Passed(submit_client.PassInterface())));
+}
+
 base::android::ScopedJavaGlobalRef<jobject> VrShell::TakeContentSurface(
     JNIEnv* env,
     const JavaParamRef<jobject>& obj) {
   content_compositor_->SurfaceChanged(nullptr);
   base::android::ScopedJavaGlobalRef<jobject> surface(env, content_surface_);
   content_surface_ = nullptr;
   return surface;
 }
 
 void VrShell::RestoreContentSurface(JNIEnv* env,
@@ skipping 14 matching lines @@
 }
 
 void VrShell::ContentSurfaceChanged(jobject surface) {
   content_surface_ = surface;
   content_compositor_->SurfaceChanged(surface);
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_VrShellImpl_contentSurfaceChanged(env, j_vr_shell_.obj());
 }
 
 void VrShell::GvrDelegateReady() {
-  PostToGlThreadWhenReady(base::Bind(
-      &VrShellGl::SetSubmitClient, gl_thread_->GetVrShellGl(),
-      base::Passed(
-          delegate_provider_->TakeSubmitFrameClient().PassInterface())));
   delegate_provider_->SetPresentingDelegate(this, gvr_api_);

[tiborg, 2017/03/24 21:58:51]

It would be helpful if this call was made in the constructor of VrShell. By
doing so, the presenting delegate in VrShellDelegate would be already set by the
time SetPresentResult is called. However, moving this to the constructor breaks
entering VRShell from 2D pages. The rendering does not start. Is there a way to
make this work?

[mthiesse, 2017/03/30 15:29:46]

What do you mean by the rendering doesn't start? How are you even moving this to
the constructor, when you don't have a submit client when not presenting?

[tiborg, 2017/03/30 22:19:57]

It goes into the binocular view but it does not render any elements. This call
doesn't need a submit client. The submit client is passed once a present request
is successful. Is was just wondering if there is an easy way to do it. If not I
would just leave it for now.

 }
 
 void VrShell::AppButtonGesturePerformed(UiInterface::Direction direction) {
   if (vr_shell_enabled_)
     html_interface_->HandleAppButtonGesturePerformed(direction);
 }
 
 void VrShell::AppButtonPressed() {
   if (vr_shell_enabled_)
     html_interface_->HandleAppButtonClicked();
@@ skipping 352 matching lines @@
            jboolean reprojected_rendering) {
   return reinterpret_cast<intptr_t>(new VrShell(
       env, obj, reinterpret_cast<ui::WindowAndroid*>(content_window_android),
       content::WebContents::FromJavaWebContents(ui_web_contents),
       reinterpret_cast<ui::WindowAndroid*>(ui_window_android), for_web_vr,
       VrShellDelegate::GetNativeVrShellDelegate(env, delegate),
       reinterpret_cast<gvr_context*>(gvr_api), reprojected_rendering));
 }
 
 }  // namespace vr_shell