Notify the browser when the page lost interest about gamepads

Source/modules/gamepad/NavigatorGamepad.cpp

Index: Source/modules/gamepad/NavigatorGamepad.cpp
diff --git a/Source/modules/gamepad/NavigatorGamepad.cpp b/Source/modules/gamepad/NavigatorGamepad.cpp
index 0b39cea0a4775edb93e83c9af4196c9516b2f78a..6333946be8a506ee5138fe2e9e63869afac7b3f6 100644
--- a/Source/modules/gamepad/NavigatorGamepad.cpp
+++ b/Source/modules/gamepad/NavigatorGamepad.cpp
@@ -228,4 +228,13 @@ void NavigatorGamepad::didRemoveAllEventListeners(LocalDOMWindow*)
     m_hasEventListener = false;
 }
 
+void NavigatorGamepad::pageVisibilityChanged()
+{
+    // Inform the embedder whether it needs to provide gamepad data for us.
+    if (page()->visibilityState() == PageVisibilityStateVisible && (m_hasEventListener || m_gamepads || m_webkitGamepads))
+        startUpdating();
+    else
+        stopUpdating();
+}
+
 } // namespace WebCore