Implement computedRole and computedName (behind a flag)

Source/core/dom/Node.cpp

Index: Source/core/dom/Node.cpp
diff --git a/Source/core/dom/Node.cpp b/Source/core/dom/Node.cpp
index c533a4185e06c4747cd9d22a83a7ae41f1a2a449..822df69eb7196554e86ed5b44b712eeaf7f3adf6 100644
--- a/Source/core/dom/Node.cpp
+++ b/Source/core/dom/Node.cpp
@@ -88,6 +88,8 @@
 #include "core/rendering/FlowThreadController.h"
 #include "core/rendering/RenderBox.h"
 #include "core/svg/graphics/SVGImage.h"
+#include "modules/accessibility/AXObject.h"

[aboxhall, 2014/12/03 00:00:13]

These are illegal includes, I had to bypass-hooks to upload this.

[dmazzoni, 2014/12/03 23:32:13]

This is as intended. What we want to do now is add a narrow, well-documented
interface to AXObjectCache.h, which is now inside of core/dom - and implemented
by AXObjectCacheImpl inside of modules/accessibility

Ideally the interface should abstract all of the accessibility details away, so
put the guts of these functions there rather than in Node.

[aboxhall, 2014/12/08 23:50:59]

Done, PTAL.

+#include "modules/accessibility/AXObjectCacheImpl.h"
 #include "platform/EventDispatchForbiddenScope.h"
 #include "platform/Partitions.h"
 #include "platform/TraceEvent.h"
@@ -1419,6 +1421,28 @@ void Node::setTextContent(const String& text)
     ASSERT_NOT_REACHED();
 }
 
+const AtomicString& Node::computedRole()
+{
+    AXObjectCache* cache = document().alwaysCreateAxObjectCache();

[dmazzoni, 2014/12/03 23:32:13]

I think some sort of ScopedAXObjectCache class would be great. If accessibility
is already enabled, it wraps the existing class (by overriding the -> operator,
like a scoped_ptr), but if not it creates one in a RAII way.

[aboxhall, 2014/12/08 23:50:59]

Done, PTAL.

+    AXObjectCacheImpl* cacheImpl = toAXObjectCacheImpl(cache);
+    AXObject* axObj = cacheImpl->getOrCreate(this);
+    if (axObj == NULL)
+      return AXObject::roleName(NoRole);

[dmazzoni, 2014/12/03 23:32:13]

nit: indentation (and below)

[aboxhall, 2014/12/08 23:50:59]

Done.

+    AccessibilityRole role = axObj->roleValue();
+    return AXObject::roleName(role);
+}
+
+const String Node::computedText()
+{
+    AXObjectCache* cache = document().alwaysCreateAxObjectCache();
+    AXObjectCacheImpl* cacheImpl = toAXObjectCacheImpl(cache);
+    AXObject* axObj = cacheImpl->getOrCreate(this);
+    if (axObj == NULL)
+        return String();
+    // TODO(aboxhall): figure out why this is crashing

[dmazzoni, 2014/12/03 23:32:13]

Probably need to layout first. We require layout is clean before calling any
AXObject accessors.

See WebAXObject::updateLayoutAndCheckValidity for more info, but I think you
want something like:

document().topDocument().view()->updateLayoutAndStyleIfNeededRecursive();

[aboxhall, 2014/12/08 23:50:59]

Done.

+    return axObj->title();
+}
+
 bool Node::offsetInCharacters() const
 {
     return false;