Resolve direction correctly when dir attribute is not in a defined state

Source/core/html/HTMLElement.cpp

Index: Source/core/html/HTMLElement.cpp
diff --git a/Source/core/html/HTMLElement.cpp b/Source/core/html/HTMLElement.cpp
index f9dff426403e18215fdd92b3f3597386140f0978..d50a2cc97fbfbb428865b40f3bbaa26984b3e912 100644
--- a/Source/core/html/HTMLElement.cpp
+++ b/Source/core/html/HTMLElement.cpp
@@ -188,10 +188,11 @@ void HTMLElement::collectStyleForPresentationAttribute(const QualifiedName& name
         if (equalIgnoringCase(value, "auto"))
             addPropertyToPresentationAttributeStyle(style, CSSPropertyUnicodeBidi, unicodeBidiAttributeForDirAuto(this));
         else {
-            if (isValidDirAttribute(value))
+            if (!isValidDirAttribute(value)) {

[tkent, 2014/09/09 06:37:00]

Looks incorrect.
If the value is "auto", we need to call directionalityIfhasDirAutoAttribute().

Probably this code block should be just
    addPropertyToPresentationAttributeStyle(style, CSSPropertyDirection,
direction() == RTL ? "rtl" : "ltr");

[esprehn, 2014/09/09 10:20:13]

Doesn't that happen inside the direction() method?

[Sunil Ratnu, 2014/09/09 10:41:57]

This check is for the case when the dir attribute is missing or has an invalid
value in which case we go on to search for the directionality of the parent.

Earlier, what we used to do is that whenever we encountered an invalid dir
attribute, we used to set the value to "ltr"

directionalityIfhasDirAutoAttribute() gets called inside the direction() method.

+                addPropertyToPresentationAttributeStyle(style, CSSPropertyDirection, direction());
+            } else {
                 addPropertyToPresentationAttributeStyle(style, CSSPropertyDirection, value);
-            else
-                addPropertyToPresentationAttributeStyle(style, CSSPropertyDirection, "ltr");
+            }
             if (!hasTagName(bdiTag) && !hasTagName(bdoTag) && !hasTagName(outputTag))
                 addPropertyToPresentationAttributeStyle(style, CSSPropertyUnicodeBidi, CSSValueEmbed);
         }
@@ -683,6 +684,26 @@ TextDirection HTMLElement::directionalityIfhasDirAutoAttribute(bool& isAuto) con
     return directionality();
 }
 
+String HTMLElement::direction() const

[tkent, 2014/09/09 06:37:00]

This function should return TextDirection because it returns either of "rtl" or
"ltr".

Also, please add FIXME about spec compliance.

[Sunil Ratnu, 2014/09/09 10:41:57]

Done.

+{
+    for (const HTMLElement* element = this; element; element = Traversal<HTMLElement>::firstAncestor(*element)) {
+        const AtomicString& dirAttributeValue = element->fastGetAttribute(dirAttr);
+        if (dirAttributeValue.isNull())
+            continue;
+
+        if (equalIgnoringCase(dirAttributeValue, "rtl") || equalIgnoringCase(dirAttributeValue, "ltr"))
+            return dirAttributeValue;
+
+        if (equalIgnoringCase(dirAttributeValue, "auto")) {
+            bool isAuto;
+            TextDirection textDirection = element->directionalityIfhasDirAutoAttribute(isAuto);
+            return textDirection == RTL ? "rtl" : "ltr";
+        }
+    }
+
+    return "ltr";
+}
+
 TextDirection HTMLElement::directionality(Node** strongDirectionalityTextNode) const
 {
     if (isHTMLInputElement(*this)) {