Makes a handful of DataSources not replace the existing

chrome/browser/webui/chrome_url_data_manager.cc

Index: chrome/browser/webui/chrome_url_data_manager.cc
diff --git a/chrome/browser/webui/chrome_url_data_manager.cc b/chrome/browser/webui/chrome_url_data_manager.cc
index c5607833ca65ff05bb213dc8958384a5d3a3d950..d7abed2b2a25b46e6f506217fd1b45fc46c95927 100644
--- a/chrome/browser/webui/chrome_url_data_manager.cc
+++ b/chrome/browser/webui/chrome_url_data_manager.cc
@@ -48,7 +48,6 @@ ChromeURLDataManager::~ChromeURLDataManager() {
 
 void ChromeURLDataManager::AddDataSource(DataSource* source) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  registered_source_names_.insert(source->source_name());
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       NewRunnableFunction(AddDataSourceOnIOThread,
@@ -56,10 +55,6 @@ void ChromeURLDataManager::AddDataSource(DataSource* source) {
                           make_scoped_refptr(source)));
 }
 
-bool ChromeURLDataManager::IsRegistered(const std::string& name) {
-  return registered_source_names_.find(name) != registered_source_names_.end();
-}
-
 // static
 void ChromeURLDataManager::DeleteDataSources() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
@@ -149,6 +144,10 @@ MessageLoop* ChromeURLDataManager::DataSource::MessageLoopForRequestPath(
   return message_loop_;
 }
 
+bool ChromeURLDataManager::DataSource::ShouldReplaceExistingSource() const {
+  return true;
+}
+
 // static
 void ChromeURLDataManager::DataSource::SetFontAndTextDirection(
     DictionaryValue* localized_strings) {