Provide WebVR pose data only to the focused frame.

third_party/WebKit/Source/modules/vr/VRDisplay.h

Index: third_party/WebKit/Source/modules/vr/VRDisplay.h
diff --git a/third_party/WebKit/Source/modules/vr/VRDisplay.h b/third_party/WebKit/Source/modules/vr/VRDisplay.h
index 7a3d101e1808cb49a6e3c767d55e8fe5c7298cf5..eef7b42a2ba8f545785c75aa4996c23eb29f9828 100644
--- a/third_party/WebKit/Source/modules/vr/VRDisplay.h
+++ b/third_party/WebKit/Source/modules/vr/VRDisplay.h
@@ -92,6 +92,8 @@ class VRDisplay final : public EventTargetWithInlineData,
   // ScriptWrappable implementation.
   bool hasPendingActivity() const final;
 
+  void focusChanged(bool focused);
+
   DECLARE_VIRTUAL_TRACE();
 
  protected:
@@ -148,7 +150,7 @@ class VRDisplay final : public EventTargetWithInlineData,
   Member<VREyeParameters> m_eyeParametersLeft;
   Member<VREyeParameters> m_eyeParametersRight;
   device::mojom::blink::VRPosePtr m_framePose;
-  int16_t m_frameId;
+  int16_t m_frameId = -1;
   VRLayer m_layer;
   double m_depthNear = 0.01;
   double m_depthFar = 10000.0;
@@ -167,6 +169,7 @@ class VRDisplay final : public EventTargetWithInlineData,
   bool m_displayBlurred = false;
   bool m_reenteredFullscreen = false;
   double m_timebase = -1;
+  bool m_focused = false;

[haraken, 2017/02/03 04:21:47]

It looks a bit weird that we have to introduce the boolean value on multiple
header files. Can we avoid it somehow?

[mthiesse, 2017/02/03 15:54:20]

Yes, done.

 
   device::mojom::blink::VRDisplayPtr m_display;