Clean up PageBoundaryRule enum.

Source/core/layout/LayoutBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
@@ skipping 2610 matching lines @@
 {
     return createAnonymousWithParentAndDisplay(parent, style()->display());
 }
 
 LayoutUnit LayoutBlock::nextPageLogicalTop(LayoutUnit logicalOffset, PageBoundaryRule pageBoundaryRule) const
 {
     LayoutUnit pageLogicalHeight = pageLogicalHeightForOffset(logicalOffset);
     if (!pageLogicalHeight)
         return logicalOffset;
 
-    // The logicalOffset is in our coordinate space.  We can add in our pushed offset.
-    LayoutUnit remainingLogicalHeight = pageRemainingLogicalHeightForOffset(logicalOffset);
-    if (pageBoundaryRule == ExcludePageBoundary)
-        return logicalOffset + (remainingLogicalHeight ? remainingLogicalHeight : pageLogicalHeight);
-    return logicalOffset + remainingLogicalHeight;
+    return logicalOffset + pageRemainingLogicalHeightForOffset(logicalOffset, pageBoundaryRule);
 }
 
 LayoutUnit LayoutBlock::pageLogicalHeightForOffset(LayoutUnit offset) const
 {
     LayoutView* layoutView = view();
     LayoutFlowThread* flowThread = flowThreadContainingBlock();
     if (!flowThread)
         return layoutView->layoutState()->pageLogicalHeight();
     return flowThread->pageLogicalHeightForOffset(offset + offsetFromLogicalTopOfFirstPage());
 }
 
 LayoutUnit LayoutBlock::pageRemainingLogicalHeightForOffset(LayoutUnit offset, PageBoundaryRule pageBoundaryRule) const
 {
     LayoutView* layoutView = view();
     offset += offsetFromLogicalTopOfFirstPage();
 
     LayoutFlowThread* flowThread = flowThreadContainingBlock();
     if (!flowThread) {
         LayoutUnit pageLogicalHeight = layoutView->layoutState()->pageLogicalHeight();
         LayoutUnit remainingHeight = pageLogicalHeight - intMod(offset, pageLogicalHeight);
-        if (pageBoundaryRule == IncludePageBoundary) {
-            // If includeBoundaryPoint is true the line exactly on the top edge of a
-            // column will act as being part of the previous column.
+        if (pageBoundaryRule == AssociateWithFormerPage) {
+            // An offset exactly at a page boundary will act as being part of the former page in
+            // question (i.e. no remaining space), rather than being part of the latter (i.e. one
+            // whole page length of remaining space).
             remainingHeight = intMod(remainingHeight, pageLogicalHeight);
         }
         return remainingHeight;
     }
 
     return flowThread->pageRemainingLogicalHeightForOffset(offset, pageBoundaryRule);
 }
 
 void LayoutBlock::setPageBreak(LayoutUnit offset, LayoutUnit spaceShortage)
 {
@@ skipping 252 matching lines @@
 void LayoutBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const LayoutObject* obj) const
 {
     showLayoutObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace blink