Re-land^2 WebVR compositor bypass via BrowserMain context + mailbox

device/vr/test/fake_vr_device.h

Index: device/vr/test/fake_vr_device.h
diff --git a/device/vr/test/fake_vr_device.h b/device/vr/test/fake_vr_device.h
index 178610eaacccb3238c582e93013b4402d0da1806..504994e26a135a743482f702bcb1da374905b986 100644
--- a/device/vr/test/fake_vr_device.h
+++ b/device/vr/test/fake_vr_device.h
@@ -30,7 +30,8 @@ class FakeVRDevice : public VRDevice {
   void RequestPresent(const base::Callback<void(bool)>& callback) override;
   void SetSecureOrigin(bool secure_origin) override;
   void ExitPresent() override;
-  void SubmitFrame(mojom::VRPosePtr pose) override;
+  void SubmitFrame(mojom::VRPosePtr pose,
+                   mojom::VRSubmitFrameClientPtr submit_client) override;
   void UpdateLayerBounds(int16_t frame_index,
                          mojom::VRLayerBoundsPtr leftBounds,
                          mojom::VRLayerBoundsPtr rightBounds) override;