WebVR: Fix missing sample collection for prediction timing

chrome/browser/android/vr_shell/vr_shell_gl.h

 // 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.
 
 #ifndef CHROME_BROWSER_ANDROID_VR_SHELL_VR_SHELL_GL_H_
 #define CHROME_BROWSER_ANDROID_VR_SHELL_VR_SHELL_GL_H_
 
 #include <memory>
 #include <queue>
 #include <utility>
@@ skipping 233 matching lines @@
   UiElement* input_locked_element_ = nullptr;
   bool in_scroll_ = false;
   bool in_click_ = false;
 
   int content_tex_css_width_ = 0;
   int content_tex_css_height_ = 0;
   gfx::Size content_tex_physical_size_ = {0, 0};
   gfx::Size webvr_surface_size_ = {0, 0};
 
   std::vector<vr::Mat4f> webvr_head_pose_;
+  std::vector<base::TimeTicks> webvr_time_pose_;
+  std::vector<base::TimeTicks> webvr_time_js_submit_;
   bool web_vr_mode_;
   bool ready_to_draw_ = false;
   bool surfaceless_rendering_;
   bool daydream_support_;
 
   std::unique_ptr<VrController> controller_;
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   base::CancelableClosure vsync_task_;
   base::TimeTicks vsync_timebase_;
@@ skipping 25 matching lines @@
   gfx::Point3F pointer_start_;
 
   base::WeakPtrFactory<VrShellGl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(VrShellGl);
 };
 
 }  // namespace vr_shell
 
 #endif  // CHROME_BROWSER_ANDROID_VR_SHELL_VR_SHELL_GL_H_