Propagate viewport intersection across OOPIFs at the correct time

third_party/WebKit/Source/core/frame/FrameView.cpp

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index b1e236624b47a9fe10155869a491d587e64eb1d4..290a541e83f0b1e7f97e7efcb0c9964bd6aeb4a0 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -4877,8 +4877,11 @@ void FrameView::UpdateViewportIntersectionsForSubtree(
 
   for (Frame* child = frame_->Tree().FirstChild(); child;
        child = child->Tree().NextSibling()) {
-    if (!child->IsLocalFrame())
+    if (child->IsRemoteFrame()) {
+      if (RemoteFrameView* view = ToRemoteFrame(child)->View())
+        view->UpdateRemoteViewportIntersection();
       continue;
+    }
     if (FrameView* view = ToLocalFrame(child)->View())
       view->UpdateViewportIntersectionsForSubtree(target_state);
   }