[css-align] New CSS Value 'normal' for Self Alignment

third_party/WebKit/Source/core/style/ComputedStyle.cpp

Index: third_party/WebKit/Source/core/style/ComputedStyle.cpp
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.cpp b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
index 504259b74d5d9eafac10c6fcd1c2229d6e78cba2..5bc8a80a65cfd5b8d9fa1639c55d6e5dddc7f094 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.cpp
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
@@ -186,11 +186,12 @@ StyleRecalcChange ComputedStyle::stylePropagationDiff(const ComputedStyle* oldSt
     if (oldStyle->display() != newStyle->display()
         || oldStyle->hasPseudoStyle(PseudoIdFirstLetter) != newStyle->hasPseudoStyle(PseudoIdFirstLetter)
         || !oldStyle->contentDataEquivalent(newStyle)
-        || oldStyle->hasTextCombine() != newStyle->hasTextCombine()
-        || oldStyle->justifyItems() != newStyle->justifyItems()) // TODO (lajava): We must avoid this Reattach.
+        || oldStyle->hasTextCombine() != newStyle->hasTextCombine())
         return Reattach;
 
-    if (oldStyle->inheritedNotEqual(*newStyle))
+    if (oldStyle->inheritedNotEqual(*newStyle)
+        || oldStyle->alignItems() != newStyle->alignItems()
+        || oldStyle->justifyItems() != newStyle->justifyItems())
         return Inherit;
 
     if (*oldStyle == *newStyle)
@@ -202,30 +203,41 @@ StyleRecalcChange ComputedStyle::stylePropagationDiff(const ComputedStyle* oldSt
     return NoInherit;
 }
 
-ItemPosition ComputedStyle::resolveAlignment(const ComputedStyle& parentStyle, const ComputedStyle& childStyle, ItemPosition resolvedAutoPositionForLayoutObject)
+static const StyleSelfAlignmentData resolvedSelfAlignment(const StyleSelfAlignmentData& value, ItemPosition normalValueBehavior)
 {
-    // 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();
+    // To avoid needing to copy the RareNonInheritedData, we could repurporse the 'auto' flag to not just mean 'auto' prior to running the StyleAdjuster but also mean 'normal' after running it.
+    if (value.position() == ItemPositionNormal || value.position() == ItemPositionAuto)
+        return {normalValueBehavior, OverflowAlignmentDefault};
+    return value;
 }
 
-const StyleSelfAlignmentData ComputedStyle::resolvedAlignment(const ComputedStyle& parentStyle, ItemPosition resolvedAutoPositionForLayoutObject) const
+const StyleSelfAlignmentData ComputedStyle::resolvedAlignItems(ItemPosition normalValueBehaviour) const
 {
-    // The auto keyword computes to the parent's align-items computed value, or to "stretch", if not set or "auto".
-    if (alignSelfPosition() == ItemPositionAuto) {
-        if (parentStyle.alignItemsPosition() == ItemPositionAuto)
-            return {resolvedAutoPositionForLayoutObject, OverflowAlignmentDefault};
-        return parentStyle.alignItems();
-    }
-    return alignSelf();
+    return resolvedSelfAlignment(alignItems(), normalValueBehaviour);
+}
+
+const StyleSelfAlignmentData ComputedStyle::resolvedAlignSelf(const ComputedStyle& parentStyle, ItemPosition normalValueBehaviour) const
+{
+    // The auto keyword computes to the parent's align-items computed value.
+    // We will return the behaviour of 'normal' value if needed, which is specific of each layout model.
+    if (alignSelfPosition() == ItemPositionAuto)

[Timothy Loh, 2016/05/23 05:45:39]

I think this branch is no longer needed (or correct), and this function doesn't
need to take the parent style any more.

[jfernandez, 2016/05/25 18:26:49]

I think you're right. However, we'd may need this for the cases where the style
is modified during the layout. Perhaps we should deal with those cases in a
different way, so I'll follow your suggestion.

+        return parentStyle.resolvedAlignItems(normalValueBehaviour);
+    return resolvedSelfAlignment(alignSelf(), normalValueBehaviour);
 }
 
-ItemPosition ComputedStyle::resolveJustification(const ComputedStyle& parentStyle, const ComputedStyle& childStyle, ItemPosition resolvedAutoPositionForLayoutObject)
+const StyleSelfAlignmentData ComputedStyle::resolvedJustifyItems(ItemPosition normalValueBehaviour) const
+{
+    return resolvedSelfAlignment(justifyItems(), normalValueBehaviour);
+}
+
+
+const StyleSelfAlignmentData ComputedStyle::resolvedJustifySelf(const ComputedStyle& parentStyle, ItemPosition normalValueBehaviour) const
 {
-    if (childStyle.justifySelfPosition() == ItemPositionAuto)
-        return (parentStyle.justifyItemsPosition() == ItemPositionAuto) ? resolvedAutoPositionForLayoutObject : parentStyle.justifyItemsPosition();
-    return childStyle.justifySelfPosition();
+    // The auto keyword computes to the parent's justify-items computed value.
+    // We will return the behaviour of 'normal' value if needed, which is specific of each layout model.
+    if (justifySelfPosition() == ItemPositionAuto)

[Timothy Loh, 2016/05/23 05:45:39]

this one too

[jfernandez, 2016/05/25 18:26:49]

Done.

+        return parentStyle.resolvedJustifyItems(normalValueBehaviour);
+    return resolvedSelfAlignment(justifySelf(), normalValueBehaviour);
 }
 
 static inline ContentPosition resolvedContentAlignmentPosition(const StyleContentAlignmentData& value, const StyleContentAlignmentData& normalValueBehavior)