Include viewport visibility checks for autoplay experiment.

third_party/WebKit/Source/core/layout/LayoutView.cpp

Index: third_party/WebKit/Source/core/layout/LayoutView.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutView.cpp b/third_party/WebKit/Source/core/layout/LayoutView.cpp
index 3056632e4b2a3752155b6093ba48bd3bbcd180bc..5313853971f78c318f8c62e23ac8dded92e9d190 100644
--- a/third_party/WebKit/Source/core/layout/LayoutView.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutView.cpp
@@ -29,10 +29,12 @@
 #include "core/frame/Settings.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/html/HTMLIFrameElement.h"
+#include "core/html/HTMLVideoElement.h"
 #include "core/inspector/InspectorTraceEvents.h"
 #include "core/layout/HitTestResult.h"
 #include "core/layout/LayoutFlowThread.h"
 #include "core/layout/LayoutGeometryMap.h"
+#include "core/layout/LayoutMedia.h"
 #include "core/layout/LayoutPart.h"
 #include "core/layout/LayoutQuote.h"
 #include "core/layout/LayoutScrollbarPart.h"
@@ -947,4 +949,24 @@ void LayoutView::willBeDestroyed()
     m_compositor.clear();
 }
 
+void LayoutView::registerMediaForPositionChangeNotification(LayoutMedia& media)
+{
+    if (!m_mediaForPositionNotification.contains(&media))
+        m_mediaForPositionNotification.append(&media);
+}
+
+void LayoutView::unregisterMediaForPositionChangeNotification(LayoutMedia& media)
+{
+    size_t at = m_mediaForPositionNotification.find(&media);
+    if (at != kNotFound)
+        m_mediaForPositionNotification.remove(at);
+}
+
+void LayoutView::sendMediaPositionChangeNotifications(const IntRect& visibleRect)
+{
+    for (auto& media : m_mediaForPositionNotification) {
+        media->notifyPositionMayHaveChanged(visibleRect);
+    }
+}
+
 } // namespace blink