Move some accessibility methods, enums and interfaces into the content/public API.

content/public/common/accessibility_mode.h

+// Copyright (c) 2013 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 CONTENT_PUBLIC_COMMON_ACCESSIBILITY_MODE_H_
+#define CONTENT_PUBLIC_COMMON_ACCESSIBILITY_MODE_H_
+
+namespace content {
+
+enum AccessibilityMode {
+  // WebKit accessibility is off and no accessibility information is
+  // sent from the renderer to the browser process.
+  ACCESSIBILITY_MODE_OFF,
+
+  // WebKit accessibility is on, but only limited information about
+  // editable text nodes is sent to the browser process. Useful for
+  // implementing limited UIA on tablets.
+  ACCESSIBILITY_MODE_EDITABLE_TEXT_ONLY,
+
+  // WebKit accessibility is on, and the full accessibility tree is synced
+  // to the browser process. Useful for screen readers and magnifiers.
+  ACCESSIBILITY_MODE_COMPLETE,
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_COMMON_ACCESSIBILITY_MODE_H_