Implement the inert attribute

third_party/WebKit/Source/modules/accessibility/AXObject.h

 /*
  * Copyright (C) 2008, 2009, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nuanti Ltd.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 341 matching lines @@
 
 enum AXIgnoredReason {
     AXActiveModalDialog,
     AXAncestorDisallowsChild,
     AXAncestorIsLeafNode,
     AXAriaHidden,
     AXAriaHiddenRoot,
     AXEmptyAlt,
     AXEmptyText,
     AXInert,
+    AXInertRoot,

[dmazzoni, 2016/06/29 17:00:56]

I wonder if AXInInertSubtree would be more clear (and similarly for
AXAriaHiddenRoot)?

After not looking at this code for a while, I remembered the difference between
AXAriaHidden and AXAriaHiddenRoot but I couldn't recall which one *is* the root
and which one is hidden *because* of a root.

     AXInheritsPresentation,
     AXLabelContainer,
     AXLabelFor,
     AXNotRendered,
     AXNotVisible,
     AXPresentationalRole,
     AXProbablyPresentational,
     AXStaticTextUsedAsNameFor,
     AXUninteresting
 };
@@ skipping 283 matching lines @@
     virtual bool canSetSelectedAttribute() const { return false; }
 
     // Whether objects are ignored, i.e. not included in the tree.
     bool accessibilityIsIgnored() const;
     typedef HeapVector<IgnoredReason> IgnoredReasons;
     virtual bool computeAccessibilityIsIgnored(IgnoredReasons* = nullptr) const { return true; }
     bool accessibilityIsIgnoredByDefault(IgnoredReasons* = nullptr) const;
     AXObjectInclusion accessibilityPlatformIncludesObject() const;
     virtual AXObjectInclusion defaultObjectInclusion(IgnoredReasons* = nullptr) const;
     bool isInertOrAriaHidden() const;
+    const AXObject* inertRoot() const;
     const AXObject* ariaHiddenRoot() const;
     bool computeIsInertOrAriaHidden(IgnoredReasons* = nullptr) const;
     bool isDescendantOfLeafNode() const;
     AXObject* leafNodeAncestor() const;
     bool isDescendantOfDisabledNode() const;
     const AXObject* disabledAncestor() const;
     bool lastKnownIsIgnoredValue();
     void setLastKnownIsIgnoredValue(bool);
     bool hasInheritedPresentationalRole() const;
     bool isPresentationalChild() const;
@@ skipping 321 matching lines @@
 
     static unsigned s_numberOfLiveAXObjects;
 };
 
 #define DEFINE_AX_OBJECT_TYPE_CASTS(thisType, predicate) \
     DEFINE_TYPE_CASTS(thisType, AXObject, object, object->predicate, object.predicate)
 
 } // namespace blink
 
 #endif // AXObject_h