Expose InlineTextBoxes in the accessibility tree.

public/web/WebAXObject.h

Index: public/web/WebAXObject.h
diff --git a/public/web/WebAXObject.h b/public/web/WebAXObject.h
index e8369126631b6fdb304a0d858244e90db34b0da5..2d2f5cb9c8e53bc4b2a93df03250e0b02f13d571 100644
--- a/public/web/WebAXObject.h
+++ b/public/web/WebAXObject.h
@@ -79,6 +79,9 @@ public:
     BLINK_EXPORT void startCachingComputedObjectAttributesUntilTreeMutates();
     BLINK_EXPORT void stopCachingComputedObjectAttributes();
 
+    // Temporary: this flag will only be toggleable until Chromium has it on by default.
+    BLINK_EXPORT static void enableInlineTextBoxAccessibility();
+
     BLINK_EXPORT int axID() const;
 
     // Update the underlying tree, and return true if this object is
@@ -195,6 +198,11 @@ public:
     BLINK_EXPORT unsigned cellRowIndex() const;
     BLINK_EXPORT unsigned cellRowSpan() const;
 
+    // For an inline text box.
+    BLINK_EXPORT WebAXTextDirection textDirection() const;
+    BLINK_EXPORT void characterOffsets(WebVector<int>&) const;
+    BLINK_EXPORT void wordBoundaries(WebVector<int>& starts, WebVector<int>& ends) const;
+
     // Make this object visible by scrolling as many nested scrollable views as needed.
     BLINK_EXPORT void scrollToMakeVisible() const;
     // Same, but if the whole object can't be made visible, try for this subrect, in local coordinates.