Propagate inert state to OOPIFs when a modal dialog is active

third_party/WebKit/Source/core/html/HTMLDialogElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLDialogElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLDialogElement.cpp b/third_party/WebKit/Source/core/html/HTMLDialogElement.cpp
index f5af85eb93c424bada4d34ff2055adb825e80561..208844da2d40f985016b8ddc8c9719272f93a538 100644
--- a/third_party/WebKit/Source/core/html/HTMLDialogElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLDialogElement.cpp
@@ -81,6 +81,13 @@ static void SetFocusForDialog(HTMLDialogElement* dialog) {
 }
 
 static void InertSubtreesChanged(Document& document) {
+  // TODO(kenrb): Am I correct in thinking that this will never get called on
+  // and element that is in a frame that is already inert? If not, we
+  // need to get the embedding frame's inert value and use that instead of
+  // false.
+  if (document.GetFrame())
+    document.GetFrame()->SetIsInert(false);
+
   // When a modal dialog opens or closes, nodes all over the accessibility
   // tree can change inertness which means they must be added or removed from
   // the tree. The most foolproof way is to clear the entire tree and rebuild