Speculative fix for crash in DOMUIThumbnailSource.

chrome/browser/dom_ui/chrome_url_data_manager.cc

Index: chrome/browser/dom_ui/chrome_url_data_manager.cc
diff --git a/chrome/browser/dom_ui/chrome_url_data_manager.cc b/chrome/browser/dom_ui/chrome_url_data_manager.cc
index 3f50a11506500d60182a1d74f36e79e5191fb9da..ac4312eab0d02f0ce87bc31a96cdc7dd5d254050 100644
--- a/chrome/browser/dom_ui/chrome_url_data_manager.cc
+++ b/chrome/browser/dom_ui/chrome_url_data_manager.cc
@@ -9,6 +9,7 @@
 #include "base/i18n/rtl.h"
 #include "base/message_loop.h"
 #include "base/path_service.h"
+#include "base/ref_counted_memory.h"
 #include "base/singleton.h"
 #include "base/string_util.h"
 #include "base/thread.h"
@@ -270,6 +271,14 @@ void ChromeURLDataManager::DataAvailable(
   }
 }
 
+ChromeURLDataManager::DataSource::DataSource(const std::string& source_name,
+                                             MessageLoop* message_loop)
+    : source_name_(source_name), message_loop_(message_loop) {
+}
+
+ChromeURLDataManager::DataSource::~DataSource() {
+}
+
 void ChromeURLDataManager::DataSource::SendResponse(
     RequestID request_id,
     RefCountedMemory* bytes) {