[WIP] Implement flexbox spec behavior for flex factor sum between 0 and 1

Source/core/layout/LayoutFlexibleBox.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 56 matching lines @@
 
     LayoutBox* child;
     LayoutUnit childSize;
 };
 
 
 LayoutFlexibleBox::LayoutFlexibleBox(Element* element)
     : LayoutBlock(element)
     , m_orderIterator(this)
     , m_numberOfInFlowChildrenOnFirstLine(-1)
+    , m_originalAvailableFreeSpaceInitialized(false)
+    , m_originalAvailableFreeSpace(0)
 {
     ASSERT(!childrenInline());
 }
 
 LayoutFlexibleBox::~LayoutFlexibleBox()
 {
 }
 
 LayoutFlexibleBox* LayoutFlexibleBox::createAnonymous(Document* document)
 {
@@ skipping 867 matching lines @@
     for (size_t i = 0; i < children.size(); ++i) {
         LayoutBox* child = children[i];
         if (child->isOutOfFlowPositioned()) {
             childSizes.append(0);
             continue;
         }
 
         if (inflexibleItems.contains(child)) {
             childSizes.append(inflexibleItems.get(child));
         } else {
+            if (!m_originalAvailableFreeSpaceInitialized) {
+                m_originalAvailableFreeSpace = availableFreeSpace;
+                m_originalAvailableFreeSpaceInitialized = true;
+            }
+            if (totalFlexGrow < 1.0f) {
+                LayoutUnit desiredPortionOfOriginalFreeSpace = LayoutUnit(m_originalAvailableFreeSpace * totalFlexGrow);
+                if (availableFreeSpace > 0)
+                    availableFreeSpace = std::min(availableFreeSpace, desiredPortionOfOriginalFreeSpace);
+                else
+                    availableFreeSpace = std::max(availableFreeSpace, desiredPortionOfOriginalFreeSpace);
+            }
+
             LayoutUnit childInnerFlexBaseSize = computeInnerFlexBaseSizeForChild(*child);
             LayoutUnit childSize = childInnerFlexBaseSize;
             double extraSpace = 0;
             bool childShrunk = false;
             if (availableFreeSpace > 0 && totalFlexGrow > 0 && flexSign == PositiveFlexibility && std::isfinite(totalFlexGrow)) {
                 extraSpace = availableFreeSpace * child->style()->flexGrow() / totalFlexGrow;
             } else if (availableFreeSpace < 0 && totalWeightedFlexShrink > 0 && flexSign == NegativeFlexibility && std::isfinite(totalWeightedFlexShrink) && child->style()->flexShrink()) {
                 extraSpace = availableFreeSpace * child->style()->flexShrink() * childInnerFlexBaseSize / totalWeightedFlexShrink;
                 childShrunk = true;
             }
@@ skipping 483 matching lines @@
             ASSERT(child);
             LayoutUnit lineCrossAxisExtent = lineContexts[lineNumber].crossAxisExtent;
             LayoutUnit originalOffset = lineContexts[lineNumber].crossAxisOffset - crossAxisStartEdge;
             LayoutUnit newOffset = contentExtent - originalOffset - lineCrossAxisExtent;
             adjustAlignmentForChild(*child, newOffset - originalOffset);
         }
     }
 }
 
 }