Allow createLocalChild to specify previous sibling frame.

Source/web/WebFrame.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 "public/web/WebFrame.h"
 
 #include "bindings/core/v8/WindowProxyManager.h"
 #include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
@@ skipping 124 matching lines @@
 
 void WebFrame::setOpener(WebFrame* opener)
 {
     if (m_opener)
         m_opener->m_openedFrameTracker->remove(this);
     if (opener)
         opener->m_openedFrameTracker->add(this);
     m_opener = opener;
 }
 
-void WebFrame::appendChild(WebFrame* child)
+void WebFrame::insertAfter(WebFrame* newChild, WebFrame* previousSibling)
 {
-    // FIXME: Original code asserts that the frames have the same Page. We
-    // should add an equivalent check... figure out what.
-    child->m_parent = this;
-    WebFrame* oldLast = m_lastChild;
-    m_lastChild = child;
+    newChild->m_parent = this;
 
-    if (oldLast) {
-        child->m_previousSibling = oldLast;
-        oldLast->m_nextSibling = child;
+    WebFrame* next;
+    if (!previousSibling) {
+        // Insert at the beginning if no previous sibling is specified.
+        next = m_firstChild;
+        m_firstChild = newChild;
     } else {
-        m_firstChild = child;
+        ASSERT(previousSibling->m_parent == this);
+        next = previousSibling->m_nextSibling;
+        previousSibling->m_nextSibling = newChild;
+        newChild->m_previousSibling = previousSibling;
+    }
+
+    if (next) {
+        newChild->m_nextSibling = next;
+        next->m_previousSibling = newChild;
+    } else {
+        m_lastChild = newChild;
     }
 
     toCoreFrame(this)->tree().invalidateScopedChildCount();
     toCoreFrame(this)->host()->incrementSubframeCount();
 }
 
+void WebFrame::appendChild(WebFrame* child)
+{
+    // TODO(dcheng): Original code asserts that the frames have the same Page.
+    // We should add an equivalent check... figure out what.
+    insertAfter(child, m_lastChild);
+}
+
 void WebFrame::removeChild(WebFrame* child)
 {
     child->m_parent = 0;
 
     if (m_firstChild == child)
         m_firstChild = child->m_nextSibling;
     else
         child->m_previousSibling->m_nextSibling = child->m_nextSibling;
 
     if (m_lastChild == child)
@@ skipping 144 matching lines @@
     bool WebFrame::isFrameAlive(VisitorDispatcher visitor, const WebFrame* frame) { return isFrameAliveImpl(visitor, frame); } \
     void WebFrame::clearWeakFrames(VisitorDispatcher visitor) { clearWeakFramesImpl(visitor); }
 
 DEFINE_VISITOR_METHOD(Visitor*)
 DEFINE_VISITOR_METHOD(InlinedGlobalMarkingVisitor)
 
 #undef DEFINE_VISITOR_METHOD
 #endif
 
 } // namespace blink