Allow createLocalChild to specify previous sibling frame.

Source/web/WebRemoteFrameImpl.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "web/WebRemoteFrameImpl.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/RemoteFrame.h"
 #include "core/frame/Settings.h"
@@ skipping 696 matching lines @@
     ASSERT_NOT_REACHED();
     return false;
 }
 
 WebString WebRemoteFrameImpl::layerTreeAsText(bool showDebugInfo) const
 {
     ASSERT_NOT_REACHED();
     return WebString();
 }
 
+// TODO(alexmos): Remove once Chromium side is updated to take previous sibling.
 WebLocalFrame* WebRemoteFrameImpl::createLocalChild(const WebString& name, WebSandboxFlags sandboxFlags, WebFrameClient* client)
 {
+    return createLocalChild(name, sandboxFlags, client, lastChild());
+}
+
+WebLocalFrame* WebRemoteFrameImpl::createLocalChild(const WebString& name, WebSandboxFlags sandboxFlags, WebFrameClient* client, WebFrame* previousSibling)
+{
     WebLocalFrameImpl* child = toWebLocalFrameImpl(WebLocalFrame::create(client));
     WillBeHeapHashMap<WebFrame*, OwnPtrWillBeMember<FrameOwner>>::AddResult result =
         m_ownersForChildren.add(child, RemoteBridgeFrameOwner::create(child, static_cast<SandboxFlags>(sandboxFlags)));
-    appendChild(child);
+    insertAfter(child, previousSibling);
     // FIXME: currently this calls LocalFrame::init() on the created LocalFrame, which may
     // result in the browser observing two navigations to about:blank (one from the initial
     // frame creation, and one from swapping it into the remote process). FrameLoader might
     // need a special initialization function for this case to avoid that duplicate navigation.
     child->initializeCoreFrame(frame()->host(), result.storedValue->value.get(), name, nullAtom);
     // Partially related with the above FIXME--the init() call may trigger JS dispatch. However,
     // if the parent is remote, it should never be detached synchronously...
     ASSERT(child->frame());
     return child;
 }
@@ skipping 69 matching lines @@
 {
     frame()->setIsLoading(false);
     if (parent() && parent()->isWebLocalFrame()) {
         WebLocalFrameImpl* parentFrame =
             toWebLocalFrameImpl(parent()->toWebLocalFrame());
         parentFrame->frame()->loader().checkCompleted();
     }
 }
 
 } // namespace blink