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Bug 512336. Make frame lists doubly-linked. r=roc,fantasai

This commit is contained in:
Boris Zbarsky 2009-10-02 12:27:37 -04:00
Родитель 95fd7df502
Коммит 58a379c1c0
14 изменённых файлов: 74 добавлений и 149 удалений
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32
layout/base/nsCSSFrameConstructor.cpp
Просмотреть файл

@ -2014,14 +2014,11 @@ static void
PullOutCaptionFrames(nsFrameItems& aItems, nsFrameItems& aCaptions)
{
nsIFrame *child = aItems.FirstChild();
nsIFrame* prev = nsnull;
while (child) {
nsIFrame *nextSibling = child->GetNextSibling();
if (nsGkAtoms::tableCaptionFrame == child->GetType()) {
aItems.RemoveFrame(child, prev);
aItems.RemoveFrame(child);
aCaptions.AddChild(child);
} else {
prev = child;
}
child = nextSibling;
}
@ -3463,17 +3460,15 @@ nsCSSFrameConstructor::ConstructFieldSetFrame(nsFrameConstructorState& aState,
nsFrameItems fieldsetKids;
fieldsetKids.AddChild(blockFrame);
for (nsFrameList::FrameLinkEnumerator link(childItems);
!link.AtEnd();
link.Next()) {
nsLegendFrame* legendFrame = do_QueryFrame(link.NextFrame());
for (nsFrameList::Enumerator e(childItems); !e.AtEnd(); e.Next()) {
nsLegendFrame* legendFrame = do_QueryFrame(e.get());
if (legendFrame) {
// We want the legend to be the first frame in the fieldset child list.
// That way the EventStateManager will do the right thing when tabbing
// from a selection point within the legend (bug 236071), which is
// used for implementing legend access keys (bug 81481).
// GetAdjustedParentFrame() below depends on this frame order.
childItems.RemoveFrame(link.NextFrame(), link.PrevFrame());
childItems.RemoveFrame(legendFrame);
// Make sure to reparent the legend so it has the fieldset as the parent.
fieldsetKids.InsertFrame(newFrame, nsnull, legendFrame);
break;
@ -3970,7 +3965,7 @@ nsCSSFrameConstructor::ConstructFrameFromItemInternal(FrameConstructionItem& aIt
break;
}
childItems.RemoveFrame(f, nsnull);
childItems.RemoveFrame(f);
if (wrapFrame) {
currentBlock.AddChild(f);
} else {
@ -5700,7 +5695,7 @@ FindAppendPrevSibling(nsIFrame* aParentFrame, nsIFrame* aAfterFrame)
{
if (aAfterFrame) {
NS_ASSERTION(aAfterFrame->GetParent() == aParentFrame, "Wrong parent");
return aParentFrame->GetChildList(nsnull).GetPrevSiblingFor(aAfterFrame);
return aAfterFrame->GetPrevSibling();
}
return aParentFrame->GetLastChild(nsnull);
@ -10183,7 +10178,7 @@ nsCSSFrameConstructor::WrapFramesInFirstLetterFrame(
if (parentFrame == aBlockFrame) {
// Take textFrame out of the block's frame list and substitute the
// letter frame(s) instead.
aBlockFrames.DestroyFrame(textFrame, prevFrame);
aBlockFrames.DestroyFrame(textFrame);
aBlockFrames.InsertFrames(nsnull, prevFrame, letterFrames);
}
else {
@ -10344,18 +10339,7 @@ nsCSSFrameConstructor::RemoveFloatingFirstLetterFrames(
frameToDelete = nextFrameToDelete;
}
// First find out where (in the content) the placeholder frames
// text is and its previous sibling frame, if any. Note that:
// 1) The placeholder had better be in the principal child list of
// parentFrame.
// 2) It's probably near the beginning (since we're a first-letter frame),
// so just doing a linear search for the prevSibling is ok.
// 3) Trying to use FindPreviousSibling will fail if the first-letter is in
// anonymous content (eg generated content).
const nsFrameList& siblingList(parentFrame->GetChildList(nsnull));
NS_ASSERTION(siblingList.ContainsFrame(placeholderFrame),
"Placeholder not in parent's principal child list?");
nsIFrame* prevSibling = siblingList.GetPrevSiblingFor(placeholderFrame);
nsIFrame* prevSibling = placeholderFrame->GetPrevSibling();
// Now that everything is set...
#ifdef NOISY_FIRST_LETTER

5
layout/base/nsFrameTraversal.cpp
Просмотреть файл

@ -504,10 +504,7 @@ nsFrameIterator::GetNextSiblingInner(nsIFrame* aFrame) {
nsIFrame*
nsFrameIterator::GetPrevSiblingInner(nsIFrame* aFrame) {
nsIFrame* parent = GetParentFrame(aFrame);
if (!parent)
return nsnull;
return parent->GetChildList(nsnull).GetPrevSiblingFor(aFrame);
return aFrame->GetPrevSibling();
}

44
layout/generic/nsBlockFrame.cpp
Просмотреть файл

@ -3261,7 +3261,7 @@ nsBlockFrame::ReflowBlockFrame(nsBlockReflowState& aState,
NS_ENSURE_SUCCESS(rv, rv);
}
else if (madeContinuation) {
mFrames.RemoveFrame(nextFrame, frame);
mFrames.RemoveFrame(nextFrame);
}
// Put it in our overflow list
@ -5203,30 +5203,22 @@ nsBlockFrame::DoRemoveFrame(nsIFrame* aDeletedFrame, PRUint32 aFlags)
nsIPresShell* presShell = presContext->PresShell();
// Find the line and the previous sibling that contains
// deletedFrame; we also find the pointer to the line.
// Find the line that contains deletedFrame
nsLineList::iterator line_start = mLines.begin(),
line_end = mLines.end();
nsLineList::iterator line = line_start;
PRBool searchingOverflowList = PR_FALSE;
nsIFrame* prevSibling = nsnull;
// Make sure we look in the overflow lines even if the normal line
// list is empty
TryAllLines(&line, &line_start, &line_end, &searchingOverflowList);
while (line != line_end) {
nsIFrame* frame = line->mFirstChild;
PRInt32 n = line->GetChildCount();
while (--n >= 0) {
if (frame == aDeletedFrame) {
goto found_frame;
}
prevSibling = frame;
frame = frame->GetNextSibling();
if (line->Contains(aDeletedFrame)) {
break;
}
++line;
TryAllLines(&line, &line_start, &line_end, &searchingOverflowList);
}
found_frame:;
if (line == line_end) {
NS_ERROR("can't find deleted frame in lines");
return NS_ERROR_FAILURE;
@ -5243,13 +5235,6 @@ found_frame:;
}
}
if (prevSibling && !prevSibling->GetNextSibling()) {
// We must have found the first frame in the overflow line list. So
// there is no prevSibling
prevSibling = nsnull;
}
NS_ASSERTION(!prevSibling || prevSibling->GetNextSibling() == aDeletedFrame, "bad prevSibling");
while ((line != line_end) && (nsnull != aDeletedFrame)) {
NS_ASSERTION(this == aDeletedFrame->GetParent(), "messed up delete code");
NS_ASSERTION(line->Contains(aDeletedFrame), "frame not in line");
@ -5287,13 +5272,14 @@ found_frame:;
// prevSibling will only be nsnull when we are deleting the very
// first frame in the main or overflow list.
if (searchingOverflowList) {
nsIFrame* prevSibling = aDeletedFrame->GetPrevSibling();
if (prevSibling) {
// XXXbz If we switch overflow lines to nsFrameList, we should
// change this SetNextSibling call.
prevSibling->SetNextSibling(nextFrame);
}
} else {
mFrames.RemoveFrame(aDeletedFrame, prevSibling);
mFrames.RemoveFrame(aDeletedFrame);
}
// Update the child count of the line to be accurate
@ -5385,20 +5371,10 @@ found_frame:;
line = line_end;
}
PRBool wasSearchingOverflowList = searchingOverflowList;
TryAllLines(&line, &line_start, &line_end, &searchingOverflowList);
if (NS_UNLIKELY(searchingOverflowList && !wasSearchingOverflowList &&
prevSibling)) {
// We switched to the overflow line list and we have a prev sibling
// (in the main list), in this case we don't want to pick up any
// sibling list from the deceased frames (bug 344557).
NS_ASSERTION(!prevSibling->GetNextSibling(), "Unexpected next sibling");
prevSibling = nsnull;
}
#ifdef NOISY_REMOVE_FRAME
printf("DoRemoveFrame: now on %s line=%p prevSibling=%p\n",
searchingOverflowList?"overflow":"normal", line.get(),
prevSibling);
printf("DoRemoveFrame: now on %s line=%p\n",
searchingOverflowList?"overflow":"normal", line.get());
#endif
}
}
@ -5467,7 +5443,7 @@ nsBlockFrame::StealFrame(nsPresContext* aPresContext,
prevSibling->SetNextSibling(frame->GetNextSibling());
frame->SetNextSibling(nsnull);
} else {
mFrames.RemoveFrame(frame, prevSibling);
mFrames.RemoveFrame(frame);
}
// Register removal with the line boxes

10
layout/generic/nsFrame.cpp
Просмотреть файл

@ -4770,11 +4770,10 @@ FindBlockFrameOrBR(nsIFrame* aFrame, nsDirection aDirection)
// Iterate over children and call ourselves recursively
if (aDirection == eDirPrevious) {
const nsFrameList& children(aFrame->GetChildList(nsnull));
nsIFrame* child = children.LastChild();
nsIFrame* child = aFrame->GetChildList(nsnull).LastChild();
while(child && !result.mContent) {
result = FindBlockFrameOrBR(child, aDirection);
child = children.GetPrevSiblingFor(child);
child = child->GetPrevSibling();
}
} else { // eDirNext
nsIFrame* child = aFrame->GetFirstChild(nsnull);
@ -4807,11 +4806,10 @@ nsIFrame::PeekOffsetParagraph(nsPeekOffsetStruct *aPos)
reachedBlockAncestor = PR_TRUE;
break;
}
const nsFrameList& siblings(parent->GetChildList(nsnull));
nsIFrame* sibling = siblings.GetPrevSiblingFor(frame);
nsIFrame* sibling = frame->GetPrevSibling();
while (sibling && !blockFrameOrBR.mContent) {
blockFrameOrBR = FindBlockFrameOrBR(sibling, eDirPrevious);
sibling = siblings.GetPrevSiblingFor(sibling);
sibling = sibling->GetPrevSibling();
}
if (blockFrameOrBR.mContent) {
aPos->mResultContent = blockFrameOrBR.mContent;

59
layout/generic/nsFrameList.cpp
Просмотреть файл

@ -94,7 +94,7 @@ nsFrameList::SetFrames(nsIFrame* aFrameList)
}
void
nsFrameList::RemoveFrame(nsIFrame* aFrame, nsIFrame* aPrevSiblingHint)
nsFrameList::RemoveFrame(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null ptr");
NS_PRECONDITION(ContainsFrame(aFrame), "wrong list");
@ -108,16 +108,13 @@ nsFrameList::RemoveFrame(nsIFrame* aFrame, nsIFrame* aPrevSiblingHint)
}
}
else {
nsIFrame* prevSibling = aPrevSiblingHint;
if (!prevSibling || prevSibling->GetNextSibling() != aFrame) {
prevSibling = GetPrevSiblingFor(aFrame);
}
if (prevSibling) {
prevSibling->SetNextSibling(nextFrame);
aFrame->SetNextSibling(nsnull);
if (!nextFrame) {
mLastChild = prevSibling;
}
nsIFrame* prevSibling = aFrame->GetPrevSibling();
NS_ASSERTION(prevSibling && prevSibling->GetNextSibling() == aFrame,
"Broken frame linkage");
prevSibling->SetNextSibling(nextFrame);
aFrame->SetNextSibling(nsnull);
if (!nextFrame) {
mLastChild = prevSibling;
}
}
}
@ -127,9 +124,9 @@ nsFrameList::RemoveFrameIfPresent(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null ptr");
for (FrameLinkEnumerator iter(*this); !iter.AtEnd(); iter.Next()) {
if (iter.NextFrame() == aFrame) {
RemoveFrame(aFrame, iter.PrevFrame());
for (Enumerator e(*this); !e.AtEnd(); e.Next()) {
if (e.get() == aFrame) {
RemoveFrame(aFrame);
return PR_TRUE;
}
}
@ -161,10 +158,10 @@ nsFrameList::RemoveFirstChild()
}
void
nsFrameList::DestroyFrame(nsIFrame* aFrame, nsIFrame* aPrevSiblingHint)
nsFrameList::DestroyFrame(nsIFrame* aFrame)
{
NS_PRECONDITION(aFrame, "null ptr");
RemoveFrame(aFrame, aPrevSiblingHint);
RemoveFrame(aFrame);
aFrame->Destroy();
}
@ -431,28 +428,6 @@ nsFrameList::SortByContentOrder()
mLastChild = f;
}
nsIFrame*
nsFrameList::GetPrevSiblingFor(nsIFrame* aFrame) const
{
NS_PRECONDITION(aFrame, "null ptr");
NS_PRECONDITION(mFirstChild, "GetPrevSiblingFor() on empty frame list");
if (aFrame == mFirstChild) {
return nsnull;
}
nsIFrame* frame = mFirstChild;
while (frame) {
nsIFrame* next = frame->GetNextSibling();
if (next == aFrame) {
break;
}
frame = next;
}
NS_POSTCONDITION(frame, "GetPrevSiblingFor() on wrong frame list");
return frame;
}
void
nsFrameList::ApplySetParent(nsIFrame* aParent) const
{
@ -485,7 +460,7 @@ nsFrameList::GetPrevVisualFor(nsIFrame* aFrame) const
nsIFrame* parent = mFirstChild->GetParent();
if (!parent)
return aFrame ? GetPrevSiblingFor(aFrame) : LastChild();
return aFrame ? aFrame->GetPrevSibling() : LastChild();
nsBidiLevel baseLevel = nsBidiPresUtils::GetFrameBaseLevel(mFirstChild);
nsBidiPresUtils* bidiUtils = mFirstChild->PresContext()->GetBidiUtils();
@ -504,7 +479,7 @@ nsFrameList::GetPrevVisualFor(nsIFrame* aFrame) const
// Just get the next or prev sibling, depending on block and frame direction.
nsBidiLevel frameEmbeddingLevel = nsBidiPresUtils::GetFrameEmbeddingLevel(mFirstChild);
if ((frameEmbeddingLevel & 1) == (baseLevel & 1)) {
return aFrame ? GetPrevSiblingFor(aFrame) : LastChild();
return aFrame ? aFrame->GetPrevSibling() : LastChild();
} else {
return aFrame ? aFrame->GetNextSibling() : mFirstChild;
}
@ -560,7 +535,7 @@ nsFrameList::GetNextVisualFor(nsIFrame* aFrame) const
nsIFrame* parent = mFirstChild->GetParent();
if (!parent)
return aFrame ? GetPrevSiblingFor(aFrame) : mFirstChild;
return aFrame ? aFrame->GetPrevSibling() : mFirstChild;
nsBidiLevel baseLevel = nsBidiPresUtils::GetFrameBaseLevel(mFirstChild);
nsBidiPresUtils* bidiUtils = mFirstChild->PresContext()->GetBidiUtils();
@ -581,7 +556,7 @@ nsFrameList::GetNextVisualFor(nsIFrame* aFrame) const
if ((frameEmbeddingLevel & 1) == (baseLevel & 1)) {
return aFrame ? aFrame->GetNextSibling() : mFirstChild;
} else {
return aFrame ? GetPrevSiblingFor(aFrame) : LastChild();
return aFrame ? aFrame->GetPrevSibling() : LastChild();
}
}
}

11
layout/generic/nsFrameList.h
Просмотреть файл

@ -122,12 +122,11 @@ public:
}
/**
* Take aFrame out of the frame list. This also disconnects aFrame
* from the sibling list. The frame must be non-null and present on
* this list.
* The second frame is a hint for the prev-sibling of aFrame; if the
* hint is correct, then this is O(1) time.
*/
void RemoveFrame(nsIFrame* aFrame, nsIFrame* aPrevSiblingHint = nsnull);
void RemoveFrame(nsIFrame* aFrame);
/**
* Take aFrame out of the frame list, if present. This also disconnects
@ -153,10 +152,8 @@ public:
/**
* Take aFrame out of the frame list and then destroy it.
* The frame must be non-null and present on this list.
* The second frame is a hint for the prev-sibling of aFrame; if the
* hint is correct, then this is O(1) time.
*/
void DestroyFrame(nsIFrame* aFrame, nsIFrame* aPrevSiblingHint = nsnull);
void DestroyFrame(nsIFrame* aFrame);
/**
* If aFrame is present on this list then take it out of the list and
@ -235,8 +232,6 @@ public:
PRInt32 GetLength() const;
nsIFrame* GetPrevSiblingFor(nsIFrame* aFrame) const;
/**
* If this frame list has only one frame, return that frame.
* Otherwise, return null.

13
layout/generic/nsIFrame.h
Просмотреть файл

@ -877,14 +877,22 @@ public:
}
/**
* Child frames are linked together in a singly-linked list
* Child frames are linked together in a doubly-linked list
*/
nsIFrame* GetNextSibling() const { return mNextSibling; }
void SetNextSibling(nsIFrame* aNextSibling) {
NS_ASSERTION(this != aNextSibling, "Creating a circular frame list, this is very bad.");
if (mNextSibling && mNextSibling->GetPrevSibling() == this) {
mNextSibling->mPrevSibling = nsnull;
}
mNextSibling = aNextSibling;
if (mNextSibling) {
mNextSibling->mPrevSibling = this;
}
}
nsIFrame* GetPrevSibling() const { return mPrevSibling; }
/**
* Builds the display lists for the content represented by this frame
* and its descendants. The background+borders of this element must
@ -2319,7 +2327,8 @@ protected:
nsStyleContext* mStyleContext;
nsIFrame* mParent;
private:
nsIFrame* mNextSibling; // singly-linked list of frames
nsIFrame* mNextSibling; // doubly-linked list of frames
nsIFrame* mPrevSibling; // Do not touch outside SetNextSibling!
protected:
nsFrameState mState;

5
layout/mathml/nsMathMLmoFrame.cpp
Просмотреть файл

@ -352,11 +352,10 @@ nsMathMLmoFrame::ProcessOperatorData()
mFlags &= ~NS_MATHML_OPERATOR_EMBELLISH_ANCESTOR;
// find the position of our outermost embellished container w.r.t
// its siblings (frames are singly-linked together).
const nsFrameList& frameList(parentAncestor->GetChildList(nsnull));
// its siblings.
nsIFrame* nextSibling = embellishAncestor->GetNextSibling();
nsIFrame* prevSibling = frameList.GetPrevSiblingFor(embellishAncestor);
nsIFrame* prevSibling = embellishAncestor->GetPrevSibling();
// flag to distinguish from a real infix
if (!prevSibling && !nextSibling)

5
layout/tables/nsTableFrame.cpp
Просмотреть файл

@ -1953,7 +1953,6 @@ nsTableFrame::PushChildren(const FrameArray& aFrames,
// extract the frames from the array into a sibling list
nsFrameList frames;
PRUint32 childX;
nsIFrame* prevSiblingHint = aFrames.SafeElementAt(aPushFrom - 1);
for (childX = aPushFrom; childX < aFrames.Length(); ++childX) {
nsIFrame* f = aFrames[childX];
// Don't push repeatable frames, do push non-rowgroup frames.
@ -1963,7 +1962,7 @@ nsTableFrame::PushChildren(const FrameArray& aFrames,
nsTableRowGroupFrame* rgFrame = GetRowGroupFrame(f);
NS_ASSERTION(rgFrame, "Unexpected non-row-group frame");
if (!rgFrame || !rgFrame->IsRepeatable()) {
mFrames.RemoveFrame(f, prevSiblingHint);
mFrames.RemoveFrame(f);
frames.AppendFrame(nsnull, f);
}
}
@ -1975,7 +1974,7 @@ nsTableFrame::PushChildren(const FrameArray& aFrames,
nsIFrame* firstBodyFrame = nextInFlow->GetFirstBodyRowGroupFrame();
nsIFrame* prevSibling = nsnull;
if (firstBodyFrame) {
prevSibling = nextInFlow->mFrames.GetPrevSiblingFor(firstBodyFrame);
prevSibling = firstBodyFrame->GetPrevSibling();
}
// When pushing and pulling frames we need to check for whether any
// views need to be reparented.

24
layout/xul/base/src/nsBoxFrame.cpp
Просмотреть файл

@ -2093,34 +2093,28 @@ nsBoxFrame::RelayoutChildAtOrdinal(nsBoxLayoutState& aState, nsIBox* aChild)
PRUint32 ord = aChild->GetOrdinal(aState);
nsIFrame *child = mFrames.FirstChild();
nsIFrame *curPrevSib = nsnull, *newPrevSib = nsnull;
PRBool foundPrevSib = PR_FALSE, foundNewPrevSib = PR_FALSE;
nsIFrame* child = mFrames.FirstChild();
nsIFrame* newPrevSib = nsnull;
while (child) {
if (child == aChild)
foundPrevSib = PR_TRUE;
else if (!foundPrevSib)
curPrevSib = child;
if (ord < child->GetOrdinal(aState)) {
break;
}
PRUint32 ordCmp = child->GetOrdinal(aState);
if (ord < ordCmp)
foundNewPrevSib = PR_TRUE;
else if (!foundNewPrevSib && child != aChild)
if (child != aChild) {
newPrevSib = child;
}
child = child->GetNextBox();
}
NS_ASSERTION(foundPrevSib, "aChild not in frame list?");
if (curPrevSib == newPrevSib) {
if (aChild->GetPrevSibling() == newPrevSib) {
// This box is not moving.
return NS_OK;
}
// Take |aChild| out of its old position in the child list.
mFrames.RemoveFrame(aChild, curPrevSib);
mFrames.RemoveFrame(aChild);
// Insert it after |newPrevSib| or at the start if it's null.
mFrames.InsertFrame(nsnull, newPrevSib, aChild);

2
layout/xul/base/src/nsListBoxBodyFrame.cpp
Просмотреть файл

@ -1110,7 +1110,7 @@ nsListBoxBodyFrame::ReverseDestroyRows(PRInt32& aRowsToLose)
--aRowsToLose;
nsIFrame* prevFrame;
prevFrame = mFrames.GetPrevSiblingFor(childFrame);
prevFrame = childFrame->GetPrevSibling();
RemoveChildFrame(state, childFrame);
mBottomFrame = childFrame = prevFrame;

3
layout/xul/base/src/nsSplitterFrame.cpp
Просмотреть файл

@ -874,8 +874,7 @@ nsSplitterFrameInner::UpdateState()
// Find the splitter's immediate sibling.
nsIFrame* splitterSibling;
if (newState == CollapsedBefore || mState == CollapsedBefore) {
splitterSibling =
mOuter->GetParent()->GetChildList(nsnull).GetPrevSiblingFor(mOuter);
splitterSibling = mOuter->GetPrevSibling();
} else {
splitterSibling = mOuter->GetNextSibling();
}

6
layout/xul/base/src/nsXULPopupManager.cpp
Просмотреть файл

@ -1809,7 +1809,7 @@ nsXULPopupManager::GetPreviousMenuItem(nsIFrame* aParent,
nsIFrame* currFrame = nsnull;
if (aStart)
currFrame = frames.GetPrevSiblingFor(aStart);
currFrame = aStart->GetPrevSibling();
else
currFrame = frames.LastChild();
@ -1819,7 +1819,7 @@ nsXULPopupManager::GetPreviousMenuItem(nsIFrame* aParent,
return (currFrame->GetType() == nsGkAtoms::menuFrame) ?
static_cast<nsMenuFrame *>(currFrame) : nsnull;
}
currFrame = frames.GetPrevSiblingFor(currFrame);
currFrame = currFrame->GetPrevSibling();
}
currFrame = frames.LastChild();
@ -1832,7 +1832,7 @@ nsXULPopupManager::GetPreviousMenuItem(nsIFrame* aParent,
static_cast<nsMenuFrame *>(currFrame) : nsnull;
}
currFrame = frames.GetPrevSiblingFor(currFrame);
currFrame = currFrame->GetPrevSibling();
}
// No luck. Just return our start value.

2
layout/xul/base/src/tree/src/nsTreeColFrame.cpp
Просмотреть файл

@ -130,7 +130,7 @@ nsDisplayXULTreeColSplitterTarget::HitTest(nsDisplayListBuilder* aBuilder,
const nsFrameList& frames(mFrame->GetParent()->GetChildList(nsnull));
nsIFrame* child;
if (left)
child = frames.GetPrevSiblingFor(mFrame);
child = mFrame->GetPrevSibling();
else
child = mFrame->GetNextSibling();