Expose InlineTextBoxes in the accessibility tree.

Source/core/accessibility/AccessibilityInlineTextBox.h

Index: Source/core/accessibility/AccessibilityInlineTextBox.h
diff --git a/Source/core/accessibility/AccessibilityInlineTextBox.h b/Source/core/accessibility/AccessibilityInlineTextBox.h
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index 0000000000000000000000000000000000000000..1b5cbe8369e677c6a74f76c722b5e3e8db219b62
--- /dev/null
+++ b/Source/core/accessibility/AccessibilityInlineTextBox.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2013, Google Inc. All rights reserved.
+ *
+ * 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.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef AccessibilityInlineTextBox_h
+#define AccessibilityInlineTextBox_h
+
+#include "core/accessibility/AccessibilityObject.h"
+#include "core/rendering/AbstractInlineTextBox.h"
+
+namespace WebCore {
+
+class AccessibilityInlineTextBox : public AccessibilityObject {

[eseidel, 2013/10/17 18:43:26]

So these are smart-pointers of sorts?  Like String() holds a RefPtr<StringImpl>,
this is a RefPtr around some other object with some wrapper methods.

But these are held in a global cache?  The lifetime of these objects is not
immediately obvious to me.  Presumably they're notified when the thing they're
holding goes away?  In this case, it's a RefPtr, so we keep it alive, so my
mental model must not quite be right?

[dmazzoni, 2013/10/17 20:39:20]

Some AccessibilityObjects are more like wrappers with weak pointers. In this
particular case a RefPtr was possible. The idea is that we need wrappers for
Nodes, RenderObjects, Frames, and now AbstractInlineTextBoxes, but they all
implement the same interface.
Most AXObjects have a weak ptr, like to a RenderObject. In that case the
AXObject is nulled immediately when the RenderObject is deleted. We remove our
own references to that AXObject when the parent object notifies us that its
children have changed.

In this case, we have a RefPtr, and the object we're referencing will get nulled
when the InlineTextBox goes away. We'll remove our own ref when the
AccessibilityObject corresponding to the RenderText notices that its children
have changed.

+
+private:
+    AccessibilityInlineTextBox(PassRefPtr<AbstractInlineTextBox>);
+
+public:
+    static PassRefPtr<AccessibilityInlineTextBox> create(PassRefPtr<AbstractInlineTextBox>);
+    virtual ~AccessibilityInlineTextBox();
+
+    virtual void init() OVERRIDE;
+    virtual void detach() OVERRIDE;
+
+    void setInlineTextBox(AbstractInlineTextBox* inlineTextBox) { m_inlineTextBox = inlineTextBox; }
+
+    virtual AccessibilityRole roleValue() const OVERRIDE { return InlineTextBoxRole; }
+    virtual String stringValue() const OVERRIDE;
+    virtual void textCharacterOffsets(Vector<int>&) const OVERRIDE;
+    virtual void wordBoundaries(Vector<PlainTextRange>& words) const OVERRIDE;
+    virtual LayoutRect elementRect() const OVERRIDE;
+    virtual AccessibilityObject* parentObject() const OVERRIDE;
+    virtual AccessibilityTextDirection textDirection() const OVERRIDE;
+
+private:
+    RefPtr<AbstractInlineTextBox> m_inlineTextBox;
+    AXObjectCache* m_axObjectCache;
+
+    virtual bool computeAccessibilityIsIgnored() const;

[eseidel, 2013/10/17 18:43:26]

OVERRIDE?

[dmazzoni, 2013/10/17 20:39:20]

Done.

+};
+
+} // namespace WebCore
+
+#endif // AccessibilityInlineTextBox_h