WebVR: match GVR renderbuffer resolution to canvas resolution

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 142 matching lines @@
   std::unique_ptr<gvr::BufferViewport> headlocked_right_viewport_;
   std::unique_ptr<gvr::BufferViewport> webvr_left_viewport_;
   std::unique_ptr<gvr::BufferViewport> webvr_right_viewport_;
   std::unique_ptr<gvr::SwapChain> swap_chain_;
   using BoundsPair = std::pair<gvr::Rectf, gvr::Rectf>;
   std::queue<std::pair<uint8_t, BoundsPair>> pending_bounds_;
 
   // Current sizes for the render buffers.
   gvr::Sizei render_size_primary_;
   gvr::Sizei render_size_headlocked_;
+  gvr::Sizei render_size_primary_vrshell_ = {0, 0};
+  gvr::Sizei render_size_primary_webvr_ = {0, 0};
 
   std::unique_ptr<VrShellRenderer> vr_shell_renderer_;
 
   bool touch_pending_ = false;
   gvr::Quatf controller_quat_;
 
   gvr::Vec3f target_point_;
   const ContentRectangle* target_element_ = nullptr;
   InputTarget current_input_target_ = InputTarget::NONE;
   InputTarget current_scroll_target = InputTarget::NONE;
@@ skipping 32 matching lines @@
   uint16_t last_frame_index_ = -1;
 
   base::WeakPtrFactory<VrShellGl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(VrShellGl);
 };
 
 }  // namespace vr_shell
 
 #endif  // CHROME_BROWSER_ANDROID_VR_SHELL_VR_SHELL_GL_H_