Provide WebVR pose data only to the focused frame.

third_party/WebKit/Source/modules/vr/NavigatorVR.cpp

Index: third_party/WebKit/Source/modules/vr/NavigatorVR.cpp
diff --git a/third_party/WebKit/Source/modules/vr/NavigatorVR.cpp b/third_party/WebKit/Source/modules/vr/NavigatorVR.cpp
index 076b64f97ce91586aaa57f9bb66de94042215eba..dfa7ad2027ecf79051fc6577904466a2c5185fa8 100644
--- a/third_party/WebKit/Source/modules/vr/NavigatorVR.cpp
+++ b/third_party/WebKit/Source/modules/vr/NavigatorVR.cpp
@@ -14,6 +14,7 @@
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Navigator.h"
 #include "core/frame/UseCounter.h"
+#include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "modules/vr/VRController.h"
 #include "modules/vr/VRDisplay.h"
@@ -25,6 +26,18 @@
 
 namespace blink {
 
+namespace {
+bool isFrameFocused(LocalFrame* frame) {
+  if (!frame)
+    return false;
+  Page* page = frame->page();
+  if (!page)
+    return false;
+  const FocusController& controller = page->focusController();
+  return controller.isFocused() && (controller.focusedOrMainFrame() == frame);
+}
+}  // namespace
+
 NavigatorVR* NavigatorVR::from(Document& document) {
   if (!document.frame() || !document.frame()->domWindow())
     return 0;
@@ -77,6 +90,8 @@ VRController* NavigatorVR::controller() {
 
   if (!m_controller) {
     m_controller = new VRController(this);
+    m_controller->setListeningForActivate(m_listeningForActivate);
+    m_controller->focusChanged(m_focused);
   }
 
   return m_controller;
@@ -90,13 +105,14 @@ Document* NavigatorVR::document() {
 DEFINE_TRACE(NavigatorVR) {
   visitor->trace(m_controller);
   Supplement<Navigator>::trace(visitor);
-  PageVisibilityObserver::trace(visitor);
 }
 
 NavigatorVR::NavigatorVR(Navigator& navigator)
-    : Supplement<Navigator>(navigator),
-      PageVisibilityObserver(navigator.frame()->page()) {
+    : Supplement<Navigator>(navigator) {
   navigator.frame()->domWindow()->registerEventListenerObserver(this);
+  navigator.frame()->page()->focusController().registerFocusChangedObserver(
+      this);
+  focusedFrameChanged();
 }
 
 NavigatorVR::~NavigatorVR() {}
@@ -122,13 +138,20 @@ void NavigatorVR::dispatchVRGestureEvent(VRDisplayEvent* event) {
   window->dispatchEvent(event);
 }
 
-void NavigatorVR::pageVisibilityChanged() {
-  if (!page())
+void NavigatorVR::focusedFrameChanged() {
+  if (isFrameFocused(supplementable()->frame())) {
+    if (!m_focused && m_controller) {
+      m_controller->setListeningForActivate(m_listeningForActivate);
+      m_controller->focusChanged(true);
+    }
+    m_focused = true;
     return;
-  if (m_controller) {
-    m_controller->setListeningForActivate(page()->isPageVisible() &&
-                                          m_listeningForActivate);
   }
+  if (m_focused && m_controller) {
+    m_controller->setListeningForActivate(false);
+    m_controller->focusChanged(false);
+  }
+  m_focused = false;
 }
 
 void NavigatorVR::didAddEventListener(LocalDOMWindow* window,
@@ -138,7 +161,7 @@ void NavigatorVR::didAddEventListener(LocalDOMWindow* window,
   if (eventType == EventTypeNames::vrdisplayactivate &&
       supplementable()->frame() && supplementable()->frame()->document() &&
       Fullscreen::fullscreenEnabled(*supplementable()->frame()->document())) {
-    controller()->setListeningForActivate(true);
+    controller()->setListeningForActivate(m_focused);
     m_listeningForActivate = true;
   } else if (eventType == EventTypeNames::vrdisplayconnect) {
     // If the page is listening for connection events make sure we've created a