Propagate inert state to OOPIFs when a modal dialog is active

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

Index: third_party/WebKit/Source/core/html/HTMLElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLElement.cpp b/third_party/WebKit/Source/core/html/HTMLElement.cpp
index 1f083b6d7a22177cb1eaa3d0289d3ad013c8558b..4144a269218dab7f0808443f470cef95cfcc10c4 100644
--- a/third_party/WebKit/Source/core/html/HTMLElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLElement.cpp
@@ -56,6 +56,7 @@
 #include "core/html/HTMLBRElement.h"
 #include "core/html/HTMLDimension.h"
 #include "core/html/HTMLFormElement.h"
+#include "core/html/HTMLFrameOwnerElement.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/HTMLMenuElement.h"
 #include "core/html/HTMLTemplateElement.h"
@@ -465,6 +466,8 @@ void HTMLElement::ParseAttribute(const AttributeModificationParams& params) {
     PseudoStateChanged(CSSSelector::kPseudoLang);
   } else if (params.name == inertAttr) {
     UseCounter::Count(GetDocument(), UseCounter::kInertAttribute);
+    GetDocument().GetFrame()->SetIsInert(GetDocument().LocalOwner() &&
+                                         GetDocument().LocalOwner()->IsInert());
   } else if (params.name == nonceAttr) {
     if (params.new_value != g_empty_atom)
       setNonce(params.new_value);