Change default value of aria-level to 2

According from ARIA 1.1 [1],
default value of aria-level was changed to 2.

We will return 2 as default in aria-level
if not otherwise specified.

[1] https://www.w3.org/WAI/ARIA/wiki/ARIA_1.1_Changes

Bug=688581

Change-Id: Ib03c23f96b74814fe9f52f196c6e0e417059112f
Reviewed-on: https://chromium-review.googlesource.com/670539Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Aaron Leventhal <aleventhal@chromium.org>
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#505425}

content/test/data/accessibility/aria/aria-heading-expected-android.txt

@@ -6,4 +6,4 @@ android.webkit.WebView focusable focused scrollable
 ++android.view.View role_description='heading 5' heading name='ARIA Heading 5'
 ++android.view.View role_description='heading 6' heading name='ARIA Heading 6'
 ++android.view.View
-++++android.view.View role_description='heading' heading name='Heading'
+++++android.view.View role_description='heading 2' heading name='Heading'
\ No newline at end of file

content/test/data/accessibility/aria/aria-heading-expected-blink.txt

@@ -18,6 +18,6 @@ rootWebArea
 ++++staticText name='ARIA Heading 6'
 ++++++inlineTextBox name='ARIA Heading 6'
 ++genericContainer
-++++heading name='Heading'
+++++heading name='Heading' hierarchicalLevel=2
 ++++++staticText name='Heading'
 ++++++++inlineTextBox name='Heading'
\ No newline at end of file

content/test/data/accessibility/aria/aria-heading-expected-mac.txt

@@ -12,5 +12,5 @@ AXWebArea
 ++AXHeading AXTitle='ARIA Heading 6' AXValue='6'
 ++++AXStaticText AXValue='ARIA Heading 6'
 ++AXGroup
-++++AXHeading AXTitle='Heading'
+++++AXHeading AXTitle='Heading' AXValue='2'
 ++++++AXStaticText AXValue='Heading'
\ No newline at end of file

content/test/data/accessibility/aria/aria-heading-expected-win.txt

@@ -12,5 +12,5 @@ ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE
 ++IA2_ROLE_HEADING name='ARIA Heading 6' xml-roles:heading level:6
 ++++ROLE_SYSTEM_STATICTEXT name='ARIA Heading 6'
 ++IA2_ROLE_SECTION
-++++IA2_ROLE_HEADING name='Heading' xml-roles:heading
+++++IA2_ROLE_HEADING name='Heading' xml-roles:heading level:2
 ++++++ROLE_SYSTEM_STATICTEXT name='Heading'

third_party/WebKit/LayoutTests/accessibility/heading-level-expected.txt

@@ -21,8 +21,8 @@ PASS: level is 3.
 PASS: level is 4.
 PASS: level is 5.
 PASS: level is 6.
-PASS: level is 1.
-PASS: level is 1.
+PASS: level is 2.
+PASS: level is 2.
 PASS successfullyParsed is true
 
 TEST COMPLETE

third_party/WebKit/LayoutTests/accessibility/heading-level.html

@@ -39,8 +39,8 @@
 <div class="ex" role="heading" data-expected="6" aria-level="6">X</div>
 
 <!-- A level that is specified either as 0 or as a ntegative number,should be set to 1. -->
-<div class="ex" role="heading" data-expected="1" aria-level="0">X</div>
-<div class="ex" role="heading" data-expected="1" aria-level="-1">X</div>
+<div class="ex" role="heading" data-expected="2" aria-level="0">X</div>
+<div class="ex" role="heading" data-expected="2" aria-level="-1">X</div>
 
 <!-- todo: h1 elements nested in section elements should inherit nested level. -->
 

third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp

@@ -75,6 +75,9 @@ namespace blink {
 
 using namespace HTMLNames;
 
+// In ARIA 1.1, default value of aria-level was changed to 2.
+const int kDefaultHeadingLevel = 2;
+
 AXNodeObject::AXNodeObject(Node* node, AXObjectCacheImpl& ax_object_cache)
     : AXObject(ax_object_cache),
       children_dirty_(false),
@@ -1073,7 +1076,6 @@ int AXNodeObject::HeadingLevel() const {
     if (HasAOMPropertyOrARIAAttribute(AOMUIntProperty::kLevel, level)) {
       if (level >= 1 && level <= 9)
         return level;
-      return 1;
     }
   }
 
@@ -1099,6 +1101,9 @@ int AXNodeObject::HeadingLevel() const {
   if (element.HasTagName(h6Tag))
     return 6;
 
+  if (RoleValue() == kHeadingRole)
+    return kDefaultHeadingLevel;
+
   return 0;
 }
 
@@ -1111,7 +1116,6 @@ unsigned AXNodeObject::HierarchicalLevel() const {
   if (HasAOMPropertyOrARIAAttribute(AOMUIntProperty::kLevel, level)) {
     if (level >= 1 && level <= 9)
       return level;
-    return 1;
   }
 
   // Only tree item will calculate its level through the DOM currently.