Backing out 413027 again.

layout/generic/nsFrame.cpp

@@ -5854,7 +5854,32 @@ nsFrame::RefreshSizeCache(nsBoxLayoutState& aState)
       Redraw(aState, &newRect);
     }
 
-    metrics->mBlockMinSize.height = metrics->mBlockPrefSize.height = newRect.height;
+    metrics->mBlockMinSize.height = 0;
+    // ok we need the max ascent of the items on the line. So to do this
+    // ask the block for its line iterator. Get the max ascent.
+    nsCOMPtr<nsILineIterator> lines = do_QueryInterface(static_cast<nsIFrame*>(this));
+    if (lines) 
+    {
+      metrics->mBlockMinSize.height = 0;
+      int count = 0;
+      nsIFrame* firstFrame = nsnull;
+      PRInt32 framesOnLine;
+      nsRect lineBounds;
+      PRUint32 lineFlags;
+
+      do {
+         lines->GetLine(count, &firstFrame, &framesOnLine, lineBounds, &lineFlags);
+
+         if (lineBounds.height > metrics->mBlockMinSize.height)
+           metrics->mBlockMinSize.height = lineBounds.height;
+
+         count++;
+      } while(firstFrame);
+    } else {
+      metrics->mBlockMinSize.height = desiredSize.height;
+    }
+
+    metrics->mBlockPrefSize.height = metrics->mBlockMinSize.height;
 
     if (desiredSize.ascent == nsHTMLReflowMetrics::ASK_FOR_BASELINE) {
       if (!nsLayoutUtils::GetFirstLineBaseline(this, &metrics->mBlockAscent))

layout/generic/nsGfxScrollFrame.cpp

@@ -1335,12 +1335,8 @@ nsGfxScrollFrameInner::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
   nsIFrame* kid = mOuter->GetFirstChild(nsnull);
   // Put each child's background directly onto the content list
   nsDisplayListSet scrollbarSet(aLists, aLists.Content());
-  nsMargin scrollbarSizes = GetActualScrollbarSizes();
   while (kid) {
-    if ((kid == mHScrollbarBox && scrollbarSizes.TopBottom() > 0) ||
-        (kid == mVScrollbarBox && scrollbarSizes.LeftRight() > 0) ||
-        (kid == mScrollCornerBox && scrollbarSizes.TopBottom() > 0 &&
-         scrollbarSizes.LeftRight() > 0)) {
+    if (kid != mScrolledFrame) {
       rv = mOuter->BuildDisplayListForChild(aBuilder, kid, aDirtyRect, scrollbarSet,
                                             nsIFrame::DISPLAY_CHILD_FORCE_PSEUDO_STACKING_CONTEXT);
       NS_ENSURE_SUCCESS(rv, rv);
@@ -2489,12 +2485,7 @@ nsGfxScrollFrameInner::LayoutScrollbars(nsBoxLayoutState& aState,
 {
   NS_ASSERTION(!mSupppressScrollbarUpdate,
                "This should have been suppressed");
-
-  // This code may try to set the scrollbar size to zero. That doesn't
-  // really work since XUL boxes will refuse to shrink below their
-  // minimum size. We compensate for that by refusing to paint or handle
-  // events for hidden scrollbars in our BuildDisplayList.
-
+    
   if (mVScrollbarBox) {
     NS_PRECONDITION(mVScrollbarBox->IsBoxFrame(), "Must be a box frame!");
     nsRect vRect(aScrollArea);

layout/reftests/bugs/reftest.list

@@ -720,8 +720,7 @@ random == 403134-1.html 403134-1-ref.html # bug 405377
 == 412607-1b.html 412607-1-ref.html
 == 412679-1.html 412679-1-ref.html
 == 412679-2.html 412679-2-ref.html
-== 413027-1.html 413027-1-ref.html
-== 413027-2.html 413027-2-ref.html
+# == 413027-1.html 413027-1-ref.html
 == 413286-1a.html 413286-1-ref.html
 == 413286-1b.html 413286-1-ref.html
 == 413286-1c.html 413286-1-ref.html

layout/xul/base/src/nsSprocketLayout.cpp

@@ -230,8 +230,6 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
   // we have 150 pixels left over.  |clientRect| is going to hold a width of 150 and
   // is going to be adjusted based off the value of the PACK property.  If flexible
   // objects are in the box, then the two rects will match.
-  // XXX this should really be called "frameBounds" or something, and we
-  // really only need the size
   nsRect originalClientRect(clientRect);
 
   // The frame state contains cached knowledge about our box, such as our orientation
@@ -287,11 +285,6 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
     }
   }
 
-  // Grow the frame size now if necessary
-  NS_ASSERTION(clientRect.TopLeft() == originalClientRect.TopLeft(),
-               "clientRect moved??");
-  originalClientRect.UnionRectIncludeEmpty(originalClientRect, clientRect);
-
   // With the sizes computed, now it's time to lay out our children.
   PRBool needsRedraw = PR_FALSE;
   PRBool finished;
@@ -306,6 +299,10 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
   nscoord origX = 0;
   nscoord origY = 0;
 
+  // |childResized| lets us know if a child changed its size after we attempted to lay it out at
+  // the specified size.  If this happens, we usually have to do another pass.
+  PRBool childResized = PR_FALSE;
+
   // |passes| stores our number of passes.  If for any reason we end up doing more than, say, 10
   // passes, we assert to indicate that something is seriously screwed up.
   passes = 0;
@@ -552,6 +549,9 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
                      flexes,
                      finished);
 
+        // We note that a child changed size, which means that another pass will be required.
+        childResized = PR_TRUE;
+
         // Now that a child resized, it's entirely possible that OUR rect is too small.  Now we
         // ensure that |originalClientRect| is grown to accommodate the size of |clientRect|.
         if (clientRect.width > originalClientRect.width || clientRect.height > originalClientRect.height) {
@@ -644,23 +644,25 @@ nsSprocketLayout::Layout(nsIBox* aBox, nsBoxLayoutState& aState)
     delete toDelete;
   }
 
-  // See if one of our children forced us to get bigger
-  nsRect tmpClientRect(originalClientRect);
-  nsMargin bp(0,0,0,0);
-  aBox->GetBorderAndPadding(bp);
-  tmpClientRect.Inflate(bp);
+  if (childResized) {
+    // See if one of our children forced us to get bigger
+    nsRect tmpClientRect(originalClientRect);
+    nsMargin bp(0,0,0,0);
+    aBox->GetBorderAndPadding(bp);
+    tmpClientRect.Inflate(bp);
 
-  if (tmpClientRect.width > originalSize.width || tmpClientRect.height > originalSize.height)
-  {
-    // if it did reset our bounds.
-    nsRect bounds(aBox->GetRect());
-    if (tmpClientRect.width > originalSize.width)
-      bounds.width = tmpClientRect.width;
+    if (tmpClientRect.width > originalSize.width || tmpClientRect.height > originalSize.height)
+    {
+      // if it did reset our bounds.
+      nsRect bounds(aBox->GetRect());
+      if (tmpClientRect.width > originalSize.width)
+        bounds.width = tmpClientRect.width;
 
-    if (tmpClientRect.height > originalSize.height)
-      bounds.height = tmpClientRect.height;
+      if (tmpClientRect.height > originalSize.height)
+        bounds.height = tmpClientRect.height;
 
-    aBox->SetBounds(aState, bounds);
+      aBox->SetBounds(aState, bounds);
+    }
   }
 
   // Because our size grew, we now have to readjust because of box packing.  Repack