Use ChildFrameDisconnector when detaching child frames of a LocalFrame.

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

Index: third_party/WebKit/Source/core/frame/Frame.cpp
diff --git a/third_party/WebKit/Source/core/frame/Frame.cpp b/third_party/WebKit/Source/core/frame/Frame.cpp
index 4a92e164bf5bd996b929334dce55a695e24e30ff..1c763fee1b4523a7ba75d0d6ed6732b0f6607e4f 100644
--- a/third_party/WebKit/Source/core/frame/Frame.cpp
+++ b/third_party/WebKit/Source/core/frame/Frame.cpp
@@ -78,17 +78,6 @@ void Frame::detach(FrameDetachType type)
     m_host = nullptr;
 }
 
-void Frame::detachChildren()
-{
-    typedef HeapVector<Member<Frame>> FrameVector;
-    FrameVector childrenToDetach;
-    childrenToDetach.reserveCapacity(tree().childCount());
-    for (Frame* child = tree().firstChild(); child; child = child->tree().nextSibling())
-        childrenToDetach.append(child);
-    for (const auto& child : childrenToDetach)
-        child->detach(FrameDetachType::Remove);
-}
-
 void Frame::disconnectOwnerElement()
 {
     if (m_owner) {