[CSS Grid Layout] Avoid using StyleAdjuster to resolve 'auto' values.

Source/core/style/ComputedStyle.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Adobe Systems Incorporated. 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 159 matching lines @@
     if ((!oldStyle && newStyle) || (oldStyle && !newStyle))
         return Reattach;
 
     if (!oldStyle && !newStyle)
         return NoChange;
 
     if (oldStyle->display() != newStyle->display()
         || oldStyle->hasPseudoStyle(FIRST_LETTER) != newStyle->hasPseudoStyle(FIRST_LETTER)
         || oldStyle->columnSpan() != newStyle->columnSpan()
         || !oldStyle->contentDataEquivalent(newStyle)
-        || oldStyle->hasTextCombine() != newStyle->hasTextCombine()
-        || oldStyle->justifyItems() != newStyle->justifyItems()
-        || oldStyle->alignItems() != newStyle->alignItems())
+        || oldStyle->hasTextCombine() != newStyle->hasTextCombine())
         return Reattach;
 
     if (oldStyle->inheritedNotEqual(*newStyle))
         return Inherit;
 
     if (*oldStyle == *newStyle)
         return diffPseudoStyles(*oldStyle, *newStyle);
 
     if (oldStyle->hasExplicitlyInheritedProperties())
         return Inherit;
 
     return NoInherit;
 }
 
-ItemPosition ComputedStyle::resolveAlignment(const ComputedStyle& parentStyle, const ComputedStyle& childStyle, ItemPosition resolvedAutoPositionForLayoutObject)
+ItemPosition ComputedStyle::resolvedAlignSelfPosition(const ComputedStyle& parentStyle, const ComputedStyle& childStyle, ItemPosition resolvedAutoPositionForLayoutObject)
 {
     // The auto keyword computes to the parent's align-items computed value, or to "stretch", if not set or "auto".
     if (childStyle.alignSelfPosition() == ItemPositionAuto)
         return (parentStyle.alignItemsPosition() == ItemPositionAuto) ? resolvedAutoPositionForLayoutObject : parentStyle.alignItemsPosition();
     return childStyle.alignSelfPosition();
 }
 
-ItemPosition ComputedStyle::resolveJustification(const ComputedStyle& parentStyle, const ComputedStyle& childStyle, ItemPosition resolvedAutoPositionForLayoutObject)
+OverflowAlignment ComputedStyle::resolvedAlignSelfOverflow(const ComputedStyle& parentStyle, const ComputedStyle& childStyle)
 {
+    // It computes to the parent's align-items computed value if "auto".
+    return (childStyle.alignSelfPosition() == ItemPositionAuto) ? parentStyle.alignItemsOverflowAlignment() : childStyle.alignSelfOverflowAlignment();
+}
+
+ItemPosition ComputedStyle::resolvedJustifySelfPosition(const ComputedStyle& parentStyle, const ComputedStyle& childStyle, ItemPosition resolvedAutoPositionForLayoutObject)
+{
+    // The auto keyword computes to the parent's justify-items computed value, or to "stretch", if not set or "auto".
     if (childStyle.justifySelfPosition() == ItemPositionAuto)
         return (parentStyle.justifyItemsPosition() == ItemPositionAuto) ? resolvedAutoPositionForLayoutObject : parentStyle.justifyItemsPosition();
     return childStyle.justifySelfPosition();
 }
 
+OverflowAlignment ComputedStyle::resolvedJustifySelfOverflow(const ComputedStyle& parentStyle, const ComputedStyle& childStyle)
+{
+    // It computes to the parent's justify-items computed value if "auto".
+    return (childStyle.justifySelfPosition() == ItemPositionAuto) ? parentStyle.justifyItemsOverflowAlignment() : childStyle.justifySelfOverflowAlignment();
+}
+
+ContentPosition ComputedStyle::resolvedAlignContentPosition() const
+{
+    const StyleContentAlignmentData& align = alignContent();
+    if (align.position() != ContentPositionAuto || align.distribution() != ContentDistributionDefault)
+        return align.position();
+    // 'auto' computes to 'stretch' for flexbox, hence it's managed by distribution().
+    return isDisplayFlexibleBox() ? ContentPositionAuto : ContentPositionStart;
+}
+
+ContentDistributionType ComputedStyle::resolvedAlignContentDistribution() const
+{
+    const StyleContentAlignmentData& align = alignContent();
+    if (align.position() != ContentPositionAuto || align.distribution() != ContentDistributionDefault)
+        return align.distribution();
+    return isDisplayFlexibleBox() ? ContentDistributionStretch : ContentDistributionDefault;
+}
+
+ContentPosition ComputedStyle::resolvedJustifyContentPosition() const
+{
+    const StyleContentAlignmentData& justify = justifyContent();
+    if (justify.position() != ContentPositionAuto || justify.distribution() != ContentDistributionDefault)
+        return justify.position();
+    // 'auto' computes to 'stretch' for flexbox, but since flexing in the main axis is controlled by flex, it behaves as flex-start.
+    return isDisplayFlexibleBox() ? ContentPositionFlexStart : ContentPositionStart;
+}
+
+ContentDistributionType ComputedStyle::resolvedJustifyContentDistribution() const
+{
+    // even that 'auto' computes to 'stretch' for flexbox it behaves as flex-start, hence it's managed by position().
+    return justifyContentDistribution();
+}
+
 void ComputedStyle::inheritFrom(const ComputedStyle& inheritParent, IsAtShadowBoundary isAtShadowBoundary)
 {
     if (isAtShadowBoundary == AtShadowBoundary) {
         // Even if surrounding content is user-editable, shadow DOM should act as a single unit, and not necessarily be editable
         EUserModify currentUserModify = userModify();
         rareInheritedData = inheritParent.rareInheritedData;
         setUserModify(currentUserModify);
     } else {
         rareInheritedData = inheritParent.rareInheritedData;
     }
@@ skipping 239 matching lines @@
     if (rareNonInheritedData.get() != other.rareNonInheritedData.get()) {
         if (rareNonInheritedData->m_appearance != other.rareNonInheritedData->m_appearance
             || rareNonInheritedData->marginBeforeCollapse != other.rareNonInheritedData->marginBeforeCollapse
             || rareNonInheritedData->marginAfterCollapse != other.rareNonInheritedData->marginAfterCollapse
             || rareNonInheritedData->lineClamp != other.rareNonInheritedData->lineClamp
             || rareNonInheritedData->textOverflow != other.rareNonInheritedData->textOverflow
             || rareNonInheritedData->m_wrapFlow != other.rareNonInheritedData->m_wrapFlow
             || rareNonInheritedData->m_wrapThrough != other.rareNonInheritedData->m_wrapThrough
             || rareNonInheritedData->m_shapeMargin != other.rareNonInheritedData->m_shapeMargin
             || rareNonInheritedData->m_order != other.rareNonInheritedData->m_order
-            || rareNonInheritedData->m_grid.get() != other.rareNonInheritedData->m_grid.get()
-            || rareNonInheritedData->m_gridItem.get() != other.rareNonInheritedData->m_gridItem.get()
             || rareNonInheritedData->m_textCombine != other.rareNonInheritedData->m_textCombine
             || rareNonInheritedData->hasFilters() != other.rareNonInheritedData->hasFilters())
             return true;
 
+        if ((rareNonInheritedData->m_grid.get() != other.rareNonInheritedData->m_grid.get()
+            && *rareNonInheritedData->m_grid.get() != *other.rareNonInheritedData->m_grid.get())
+            || (rareNonInheritedData->m_gridItem.get() != other.rareNonInheritedData->m_gridItem.get()
+                && *rareNonInheritedData->m_gridItem.get() != *other.rareNonInheritedData->m_gridItem.get()))
+            return true;
+
         if (rareNonInheritedData->m_deprecatedFlexibleBox.get() != other.rareNonInheritedData->m_deprecatedFlexibleBox.get()
             && *rareNonInheritedData->m_deprecatedFlexibleBox.get() != *other.rareNonInheritedData->m_deprecatedFlexibleBox.get())
             return true;
 
         if (rareNonInheritedData->m_flexibleBox.get() != other.rareNonInheritedData->m_flexibleBox.get()
             && *rareNonInheritedData->m_flexibleBox.get() != *other.rareNonInheritedData->m_flexibleBox.get())
             return true;
 
         // FIXME: We should add an optimized form of layout that just recomputes visual overflow.
         if (!rareNonInheritedData->shadowDataEquivalent(*other.rareNonInheritedData.get()))
@@ skipping 1251 matching lines @@
 }
 
 void ComputedStyle::copyChildDependentFlagsFrom(const ComputedStyle& other)
 {
     setEmptyState(other.emptyState());
     if (other.hasExplicitlyInheritedProperties())
         setHasExplicitlyInheritedProperties();
 }
 
 } // namespace blink