NTP: Prevent tab sync icons from being cached.

chrome/browser/ui/webui/session_favicon_source.cc

Index: chrome/browser/ui/webui/session_favicon_source.cc
diff --git a/chrome/browser/ui/webui/session_favicon_source.cc b/chrome/browser/ui/webui/session_favicon_source.cc
index 453fd0e0e41eeaf0ff20a59431daa588c5cce893..6d8b5cd99f78adf36d4c591c059fdecc91c4fe29 100644
--- a/chrome/browser/ui/webui/session_favicon_source.cc
+++ b/chrome/browser/ui/webui/session_favicon_source.cc
@@ -49,3 +49,9 @@ bool SessionFaviconSource::ShouldReplaceExistingSource() const {
   // requests on the floor.
   return false;
 }
+
+bool SessionFaviconSource::AllowCaching() const {
+  // Prevent responses from being cached, otherwise session favicons won't
+  // update in a timely manner.
+  return false;
+}