MacViews: Implement Force Touch/Mac dictionary lookup for Textfields.

ui/gfx/render_text_harfbuzz.cc

 // Copyright 2014 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.
 
 #include "ui/gfx/render_text_harfbuzz.h"
 
 #include <limits>
 #include <set>
 
 #include "base/i18n/bidi_line_iterator.h"
@@ skipping 1572 matching lines @@
 internal::TextRunList* RenderTextHarfBuzz::GetRunList() {
   DCHECK(!update_layout_run_list_);
   DCHECK(!update_display_run_list_);
   return text_elided() ? display_run_list_.get() : &layout_run_list_;
 }
 
 const internal::TextRunList* RenderTextHarfBuzz::GetRunList() const {
   return const_cast<RenderTextHarfBuzz*>(this)->GetRunList();
 }
 
+#if !defined(OS_MACOSX)
+bool RenderTextHarfBuzz::GetStyledStringForRange(const Range& range,
+                                                 base::string16* str) const {
+  if (obscured())
+    return false;
+  *str = GetTextFromRange(range);
+  return true;
+}
+#endif
+
 }  // namespace gfx