Use text affinity to return correct accessible line boundaries.

ui/accessibility/ax_text_utils.h

 // 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.
 
 #ifndef UI_ACCESSIBILITY_AX_TEXT_UTILS_H_
 #define UI_ACCESSIBILITY_AX_TEXT_UTILS_H_
 
 #include <stddef.h>
 
 #include <vector>
 
 #include "base/strings/string16.h"
+#include "ui/accessibility/ax_enums.h"
 #include "ui/accessibility/ax_export.h"
 
 namespace ui {
 
 // Boundaries that can be passed to FindAccessibleTextBoundary,
 // representing various visual boundaries in (potentially multi-line)
 // text. This is used by assistive technology in order to, for example,
 // retrieve the nearest word to the cursor, or retrieve all of the
 // text from the current cursor position to the end of the line.
 // These should be self-explanatory; "line" here refers to the visual
@@ skipping 18 matching lines @@
 // Convenience method needed to implement platform-specific text
 // accessibility APIs like IAccessible2. Search forwards or backwards
 // (depending on |direction|) from the given |start_offset| until the
 // given boundary is found, and return the offset of that boundary,
 // using the vector of line break character offsets in |line_breaks|.
 size_t AX_EXPORT
     FindAccessibleTextBoundary(const base::string16& text,
                                const std::vector<int>& line_breaks,
                                TextBoundaryType boundary,
                                size_t start_offset,
-                               TextBoundaryDirection direction);
+                               TextBoundaryDirection direction,
+                               AXTextAffinity affinity);
 
 }  // namespace ui
 
 #endif  // UI_ACCESSIBILITY_AX_TEXT_UTILS_H_