Remove CSS regions support, keeping a bare minimum to support "region-based" multicol.

Source/core/rendering/RenderBlockLineLayout.cpp

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All right reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 1278 matching lines @@
 
                         if (availableLogicalWidthForLine(oldLogicalHeight + adjustment, layoutState.lineInfo().isFirstLine()) != oldLineWidth) {
                             // We have to delete this line, remove all floats that got added, and let line layout re-run.
                             lineBox->deleteLine();
                             endOfLine = restartLayoutRunsAndFloatsInRange(oldLogicalHeight, oldLogicalHeight + adjustment, lastFloatFromPreviousLine, resolver, previousEndofLine);
                             continue;
                         }
 
                         setLogicalHeight(lineBox->lineBottomWithLeading());
                     }
-
-                    if (layoutState.flowThread())
-                        updateRegionForLine(lineBox);
                 }
             }
         }
 
         for (size_t i = 0; i < lineBreaker.positionedObjects().size(); ++i)
             setStaticPositions(this, lineBreaker.positionedObjects()[i]);
 
         if (!layoutState.lineInfo().isEmpty()) {
             layoutState.lineInfo().setFirstLine(false);
             clearFloats(lineBreaker.clear());
@@ skipping 98 matching lines @@
             for (RootInlineBox* line = layoutState.endLine(); line; line = line->nextRootBox()) {
                 line->attachLine();
                 if (paginated) {
                     delta -= line->paginationStrut();
                     adjustLinePositionForPagination(line, delta, layoutState.flowThread());
                 }
                 if (delta) {
                     layoutState.updateRepaintRangeFromBox(line, delta);
                     line->adjustBlockDirectionPosition(delta);
                 }
-                if (layoutState.flowThread())
-                    updateRegionForLine(line);
                 if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) {
                     Vector<RenderBox*>::iterator end = cleanLineFloats->end();
                     for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) {
                         FloatingObject* floatingObject = insertFloatingObject(*f);
                         ASSERT(!floatingObject->originatingLine());
                         floatingObject->setOriginatingLine(line);
                         setLogicalHeight(logicalTopForChild(*f) - marginBeforeForChild(*f) + delta);
                         positionNewFloats();
                     }
                 }
@@ skipping 13 matching lines @@
             LayoutUnit bottomVisualOverflow = lastRootBox()->logicalBottomVisualOverflow();
             LayoutUnit bottomLayoutOverflow = lastRootBox()->logicalBottomLayoutOverflow();
             TrailingFloatsRootInlineBox* trailingFloatsLineBox = new TrailingFloatsRootInlineBox(this);
             m_lineBoxes.appendLineBox(trailingFloatsLineBox);
             trailingFloatsLineBox->setConstructed();
             GlyphOverflowAndFallbackFontsMap textBoxDataMap;
             VerticalPositionCache verticalPositionCache;
             LayoutUnit blockLogicalHeight = logicalHeight();
             trailingFloatsLineBox->alignBoxesInBlockDirection(blockLogicalHeight, textBoxDataMap, verticalPositionCache);
             trailingFloatsLineBox->setLineTopBottomPositions(blockLogicalHeight, blockLogicalHeight, blockLogicalHeight, blockLogicalHeight);
-            trailingFloatsLineBox->setPaginatedLineWidth(availableLogicalWidthForContent(blockLogicalHeight));
+            trailingFloatsLineBox->setPaginatedLineWidth(availableLogicalWidthForContent());
             LayoutRect logicalLayoutOverflow(0, blockLogicalHeight, 1, bottomLayoutOverflow - blockLogicalHeight);
             LayoutRect logicalVisualOverflow(0, blockLogicalHeight, 1, bottomVisualOverflow - blockLogicalHeight);
             trailingFloatsLineBox->setOverflowFromLogicalRects(logicalLayoutOverflow, logicalVisualOverflow, trailingFloatsLineBox->lineTop(), trailingFloatsLineBox->lineBottom());
-            if (layoutState.flowThread())
-                updateRegionForLine(trailingFloatsLineBox);
         }
 
         const FloatingObjectSet& floatingObjectSet = m_floatingObjects->set();
         FloatingObjectSetIterator it = floatingObjectSet.begin();
         FloatingObjectSetIterator end = floatingObjectSet.end();
         if (layoutState.lastFloat()) {
             FloatingObjectSetIterator lastFloatIterator = floatingObjectSet.find(layoutState.lastFloat());
             ASSERT(lastFloatIterator != end);
             ++lastFloatIterator;
             it = lastFloatIterator;
@@ skipping 162 matching lines @@
 
     // FIXME: This entire float-checking block needs to be broken into a new function.
     bool dirtiedByFloat = false;
     if (!layoutState.isFullLayout()) {
         // Paginate all of the clean lines.
         bool paginated = view()->layoutState() && view()->layoutState()->isPaginated();
         LayoutUnit paginationDelta = 0;
         size_t floatIndex = 0;
         for (curr = firstRootBox(); curr && !curr->isDirty(); curr = curr->nextRootBox()) {
             if (paginated) {
-                if (lineWidthForPaginatedLineChanged(curr, 0, layoutState.flowThread())) {
-                    curr->markDirty();
-                    break;
-                }
                 paginationDelta -= curr->paginationStrut();
                 adjustLinePositionForPagination(curr, paginationDelta, layoutState.flowThread());
                 if (paginationDelta) {
                     if (containsFloats() || !layoutState.floats().isEmpty()) {
                         // FIXME: Do better eventually.  For now if we ever shift because of pagination and floats are present just go to a full layout.
                         layoutState.markForFullLayout();
                         break;
                     }
 
                     layoutState.updateRepaintRangeFromBox(curr, paginationDelta);
                     curr->adjustBlockDirectionPosition(paginationDelta);
                 }
-                if (layoutState.flowThread())
-                    updateRegionForLine(curr);
             }
 
             // If a new float has been inserted before this line or before its last known float, just do a full layout.
             bool encounteredNewFloat = false;
             checkFloatsInCleanLine(curr, layoutState.floats(), floatIndex, encounteredNewFloat, dirtiedByFloat);
             if (encounteredNewFloat)
                 layoutState.markForFullLayout();
 
             if (dirtiedByFloat || layoutState.isFullLayout())
                 break;
@@ skipping 132 matching lines @@
         // in a different available line width.
         for (RootInlineBox* lineBox = layoutState.endLine(); lineBox; lineBox = lineBox->nextRootBox()) {
             if (paginated) {
                 // This isn't the real move we're going to do, so don't update the line box's pagination
                 // strut yet.
                 LayoutUnit oldPaginationStrut = lineBox->paginationStrut();
                 lineDelta -= oldPaginationStrut;
                 adjustLinePositionForPagination(lineBox, lineDelta, layoutState.flowThread());
                 lineBox->setPaginationStrut(oldPaginationStrut);
             }
-            if (lineWidthForPaginatedLineChanged(lineBox, lineDelta, layoutState.flowThread()))
-                return false;
         }
     }
 
     if (!lineDelta || !m_floatingObjects)
         return true;
 
     // See if any floats end in the range along which we want to shift the lines vertically.
     LayoutUnit logicalTop = min(logicalHeight(), layoutState.endLineLogicalTop());
 
     RootInlineBox* lastLine = layoutState.endLine();
@@ skipping 238 matching lines @@
     lineGridBox->alignBoxesInBlockDirection(logicalHeight(), textBoxDataMap, verticalPositionCache);
 
     setLineGridBox(lineGridBox);
 
     // FIXME: If any of the characteristics of the box change compared to the old one, then we need to do a deep dirtying
     // (similar to what happens when the page height changes). Ideally, though, we only do this if someone is actually snapping
     // to this grid.
 }
 
 }