Revert 170347 "Convert HTMLFrameOwnerElement and FocusController..."

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
===================================================================
--- Source/core/dom/Document.cpp	(revision 170478)
+++ Source/core/dom/Document.cpp	(working copy)
@@ -986,8 +986,7 @@
 
         if (source->isFrameOwnerElement()) {
             HTMLFrameOwnerElement* frameOwnerElement = toHTMLFrameOwnerElement(source.get());
-            // FIXME(kenrb): the downcast can be removed when the FrameTree supports RemoteFrames.
-            if (frame() && frame()->tree().isDescendantOf(toLocalFrameTemporary(frameOwnerElement->contentFrame()))) {
+            if (frame() && frame()->tree().isDescendantOf(frameOwnerElement->contentFrame())) {
                 exceptionState.throwDOMException(HierarchyRequestError, "The node provided is a frame which contains this document.");
                 return nullptr;
             }
@@ -5444,9 +5443,9 @@
     Page* page = this->page();
     if (!page)
         return false;
-    if (!page->focusController().isActive() || !page->focusController().isFocused() || !page->focusController().focusedFrame()->isLocalFrame())
+    if (!page->focusController().isActive() || !page->focusController().isFocused())
         return false;
-    if (LocalFrame* focusedFrame = toLocalFrame(page->focusController().focusedFrame())) {
+    if (LocalFrame* focusedFrame = page->focusController().focusedFrame()) {
         if (focusedFrame->tree().isDescendantOf(frame()))
             return true;
     }