[Mac] Implement the system dictionary popup by implementing NSTextInput methods.

chrome/browser/renderer_host/render_widget_host_view_gtk.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 "chrome/browser/renderer_host/render_widget_host_view_gtk.h"
 
 // If this gets included after the gtk headers, then a bunch of compiler
 // errors happen because of a "#define Status int" in Xlib.h, which interacts
 // badly with net::URLRequestStatus::Status.
 #include "chrome/common/render_messages.h"
@@ skipping 720 matching lines @@
     gtk_widget_set_has_tooltip(view_.get(), FALSE);
   } else {
     gtk_widget_set_tooltip_text(view_.get(),
                                 UTF16ToUTF8(clamped_tooltip).c_str());
 #if defined(OS_CHROMEOS)
     tooltip_window_->SetTooltipText(UTF16ToWideHack(clamped_tooltip));
 #endif  // defined(OS_CHROMEOS)
   }
 }
 
-void RenderWidgetHostViewGtk::SelectionChanged(const std::string& text) {
+void RenderWidgetHostViewGtk::SelectionChanged(const std::string& text,
+                                               int start,
+                                               int end) {
   if (!text.empty()) {
     GtkClipboard* x_clipboard = gtk_clipboard_get(GDK_SELECTION_PRIMARY);
     gtk_clipboard_set_text(x_clipboard, text.c_str(), text.length());
   }
 }
 
 void RenderWidgetHostViewGtk::ShowingContextMenu(bool showing) {
   is_showing_context_menu_ = showing;
 }
 
@@ skipping 369 matching lines @@
 }
 
 // static
 RenderWidgetHostView*
     RenderWidgetHostView::GetRenderWidgetHostViewFromNativeView(
         gfx::NativeView widget) {
   gpointer user_data = g_object_get_data(G_OBJECT(widget),
                                          kRenderWidgetHostViewKey);
   return reinterpret_cast<RenderWidgetHostView*>(user_data);
 }