Fixed bad WebVR content judder when the HTTP warning was displayed

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 "base/metrics/histogram_macros.h"
 #include "chrome/browser/android/vr_shell/ui_elements.h"
 #include "chrome/browser/android/vr_shell/ui_interface.h"
 #include "chrome/browser/android/vr_shell/ui_scene.h"
@@ skipping 428 matching lines @@
     // TODO: Not sure what object_from_reference_matrix is. The new api removed
     // it. For now, removing it seems working fine.
     gvr_api_->ApplyNeckModel(head_pose, 1.0f);
   }
 
   // Bind the primary framebuffer.
   frame.BindBuffer(kFramePrimaryBuffer);
 
   if (webvr_mode_) {
     DrawWebVr();
+
+    // When using async reprojection, we need to know which pose was used in
+    // the WebVR app for drawing this frame. Due to unknown amounts of
+    // buffering in the compositor and SurfaceTexture, we read the pose number
+    // from a corner pixel. There's no point in doing this for legacy
+    // distortion rendering since that doesn't need a pose, and reading back
+    // pixels is an expensive operation. TODO(klausw): stop doing this once we
+    // have working no-compositor rendering for WebVR.
+    if (gvr_api_->GetAsyncReprojectionEnabled()) {
+      uint32_t webvr_pose_frame = GetPixelEncodedPoseIndex();
+      head_pose = webvr_head_pose_[webvr_pose_frame % kPoseRingBufferSize];
+    }
+
     // Wait for the DOM contents to be loaded before rendering to avoid drawing
     // white rectangles with no content.
     if (!webvr_secure_origin_ && IsUiTextureReady()) {
       size_t last_viewport = buffer_viewport_list_->GetSize();
       buffer_viewport_list_->SetBufferViewport(last_viewport++,
           *headlocked_left_viewport_);
       buffer_viewport_list_->SetBufferViewport(last_viewport++,
           *headlocked_right_viewport_);
 
       // Bind the headlocked framebuffer.
       frame.BindBuffer(kFrameHeadlockedBuffer);
       DrawWebVrOverlay(target_time.monotonic_system_time_nanos);
     }
-
-    // When using async reprojection, we need to know which pose was used in
-    // the WebVR app for drawing this frame. Due to unknown amounts of
-    // buffering in the compositor and SurfaceTexture, we read the pose number
-    // from a corner pixel. There's no point in doing this for legacy
-    // distortion rendering since that doesn't need a pose, and reading back
-    // pixels is an expensive operation. TODO(klausw): stop doing this once we
-    // have working no-compositor rendering for WebVR.
-    if (gvr_api_->GetAsyncReprojectionEnabled()) {
-      uint32_t webvr_pose_frame = GetPixelEncodedPoseIndex();
-      head_pose = webvr_head_pose_[webvr_pose_frame % kPoseRingBufferSize];
-    }
   } else {
     DrawVrShell(head_pose);
   }
 
   frame.Unbind();
   frame.Submit(*buffer_viewport_list_, head_pose);
 }
 
 void VrShell::DrawVrShell(const gvr::Mat4f& head_pose) {
   float screen_tilt = desktop_screen_tilt_ * M_PI / 180.0f;
@@ skipping 432 matching lines @@
            const JavaParamRef<jobject>& ui_web_contents,
            jlong ui_window_android) {
   return reinterpret_cast<intptr_t>(new VrShell(
       env, obj, content::WebContents::FromJavaWebContents(content_web_contents),
       reinterpret_cast<ui::WindowAndroid*>(content_window_android),
       content::WebContents::FromJavaWebContents(ui_web_contents),
       reinterpret_cast<ui::WindowAndroid*>(ui_window_android)));
 }
 
 }  // namespace vr_shell