Allow VRDisplay to specify which frame the layer bounds should be updated at.

chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h

Index: chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h
diff --git a/chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h b/chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h
index f95dce35c778eef42dec7d88264ee951a07f6f11..0d6a80184beddca1ea787faef96009301825dce4 100644
--- a/chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h
+++ b/chrome/browser/android/vr_shell/non_presenting_gvr_delegate.h
@@ -26,11 +26,13 @@ class NonPresentingGvrDelegate : public device::GvrDelegate,
   // GvrDelegate implementation
   void SetWebVRSecureOrigin(bool secure_origin) override {}
   void SubmitWebVRFrame() override {}
-  void UpdateWebVRTextureBounds(const gvr::Rectf& left_bounds,
+  void UpdateWebVRTextureBounds(int16_t frame_index,
+                                const gvr::Rectf& left_bounds,
                                 const gvr::Rectf& right_bounds) override {}
   void SetWebVRRenderSurfaceSize(int width, int height) override {}
   gvr::Sizei GetWebVRCompositorSurfaceSize() override {
-    return device::kInvalidRenderTargetSize; }
+    return device::kInvalidRenderTargetSize;
+  }
   gvr::GvrApi* gvr_api() override { return gvr_api_.get(); }
   void OnVRVsyncProviderRequest(
       device::mojom::VRVSyncProviderRequest request) override;
@@ -45,8 +47,10 @@ class NonPresentingGvrDelegate : public device::GvrDelegate,
   void StopVSyncLoop();
   void StartVSyncLoop();
   void OnVSync();
-  void GetVSync(const GetVSyncCallback& callback);
-  device::mojom::VRPosePtr GetPose();
+  void SendVSync(double time, GetVSyncCallback callback);
+
+  // VRVSyncProvider implementation
+  void GetVSync(const GetVSyncCallback& callback) override;
 
   std::unique_ptr<gvr::GvrApi> gvr_api_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
@@ -59,7 +63,6 @@ class NonPresentingGvrDelegate : public device::GvrDelegate,
   bool pending_vsync_ = false;
   GetVSyncCallback callback_;
   bool received_frame_ = false;
-  uint32_t pose_index_ = 1;
   mojo::Binding<device::mojom::VRVSyncProvider> binding_;
   base::WeakPtrFactory<NonPresentingGvrDelegate> weak_ptr_factory_;