Improve RenderTextWin font fallback.

ui/gfx/render_text_linux.cc

 // Copyright (c) 2011 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_linux.h"
 
 #include <pango/pangocairo.h>
 
 #include <algorithm>
 
@@ skipping 202 matching lines @@
         return SelectionModel(text().length(), caret, SelectionModel::TRAILING);
       } else {  // RTL.
         size_t caret = Utf8IndexToUtf16Index(item->offset);
         return SelectionModel(text().length(), caret, SelectionModel::LEADING);
       }
     }
   }
   return SelectionModel(0, 0, SelectionModel::LEADING);
 }
 
-bool RenderTextLinux::IsCursorablePosition(size_t position) {
+bool RenderTextLinux::IsCursorablePosition(size_t position, bool is_trailing) {

[msw, 2011/11/29 20:42:00]

|is_trailing| is unused here... does it really have a purpose?

   if (position == 0 && text().empty())
     return true;
 
   EnsureLayout();
   return (position < static_cast<size_t>(num_log_attrs_) &&
           log_attrs_[position].is_cursor_position);
 }
 
 void RenderTextLinux::UpdateLayout() {
   ResetLayout();
@@ skipping 417 matching lines @@
 size_t RenderTextLinux::Utf8IndexToUtf16Index(size_t index) const {
   int32_t utf16_index = 0;
   UErrorCode ec = U_ZERO_ERROR;
   u_strFromUTF8(NULL, 0, &utf16_index, layout_text_, index, &ec);
   DCHECK(ec == U_BUFFER_OVERFLOW_ERROR ||
          ec == U_STRING_NOT_TERMINATED_WARNING);
   return utf16_index;
 }
 
 }  // namespace gfx