ARIA role spinbutton should expose AXRole as AXIncrementor.

content/browser/accessibility/browser_accessibility_cocoa.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <execinfo.h>
 
 #import "content/browser/accessibility/browser_accessibility_cocoa.h"
 
 #include <map>
 
@@ skipping 825 matching lines @@
             1 :
             value;
 
     if (browserAccessibility_->GetBoolAttribute(
         ui::AX_ATTR_BUTTON_MIXED)) {
       value = 2;
     }
     return [NSNumber numberWithInt:value];
   } else if ([role isEqualToString:NSAccessibilityProgressIndicatorRole] ||
              [role isEqualToString:NSAccessibilitySliderRole] ||
+             [role isEqualToString:NSAccessibilityIncrementorRole] ||
              [role isEqualToString:NSAccessibilityScrollBarRole]) {
     float floatValue;
     if (browserAccessibility_->GetFloatAttribute(
             ui::AX_ATTR_VALUE_FOR_RANGE, &floatValue)) {
       return [NSNumber numberWithFloat:floatValue];
     }
   } else if ([role isEqualToString:NSAccessibilityColorWellRole]) {
     int r = browserAccessibility_->GetIntAttribute(
         ui::AX_ATTR_COLOR_VALUE_RED);
     int g = browserAccessibility_->GetIntAttribute(
@@ skipping 401 matching lines @@
         NSAccessibilityInsertionPointLineNumberAttribute,
         NSAccessibilityNumberOfCharactersAttribute,
         NSAccessibilitySelectedTextAttribute,
         NSAccessibilitySelectedTextRangeAttribute,
         NSAccessibilityVisibleCharacterRangeAttribute,
         nil]];
   } else if ([role isEqualToString:NSAccessibilityTabGroupRole]) {
     [ret addObject:NSAccessibilityTabsAttribute];
   } else if ([role isEqualToString:NSAccessibilityProgressIndicatorRole] ||
              [role isEqualToString:NSAccessibilitySliderRole] ||
+             [role isEqualToString:NSAccessibilityIncrementorRole] ||
              [role isEqualToString:NSAccessibilityScrollBarRole]) {
     [ret addObjectsFromArray:[NSArray arrayWithObjects:
         NSAccessibilityMaxValueAttribute,
         NSAccessibilityMinValueAttribute,
         NSAccessibilityOrientationAttribute,
         NSAccessibilityValueDescriptionAttribute,
         nil]];
   } else if ([subrole isEqualToString:NSAccessibilityOutlineRowSubrole]) {
     [ret addObjectsFromArray:[NSArray arrayWithObjects:
         NSAccessibilityDisclosingAttribute,
@@ skipping 206 matching lines @@
     return [super hash];
   return browserAccessibility_->GetId();
 }
 
 - (BOOL)accessibilityShouldUseUniqueId {
   return YES;
 }
 
 @end