Move WebUIMessageHandler to its own file in the public directory and put it in the content namesp...

chrome/browser/ui/webui/edit_search_engine_dialog_webui.cc

Index: chrome/browser/ui/webui/edit_search_engine_dialog_webui.cc
===================================================================
--- chrome/browser/ui/webui/edit_search_engine_dialog_webui.cc	(revision 116051)
+++ chrome/browser/ui/webui/edit_search_engine_dialog_webui.cc	(working copy)
@@ -19,12 +19,14 @@
 #include "chrome/browser/ui/search_engines/edit_search_engine_controller.h"
 #include "chrome/browser/ui/webui/theme_source.h"
 #include "chrome/common/url_constants.h"
+#include "content/browser/webui/web_ui.h"
 #include "grit/generated_resources.h"
 #include "grit/theme_resources.h"
 #include "grit/ui_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 
 using content::WebContents;
+using content::WebUIMessageHandler;
 
 namespace {
 const int kEditSearchEngineDialogWidth = 440;