Add AddCallbackForCookie method to CookieStore.

chrome/browser/prerender/prerender_cookie_store.cc

Index: chrome/browser/prerender/prerender_cookie_store.cc
diff --git a/chrome/browser/prerender/prerender_cookie_store.cc b/chrome/browser/prerender/prerender_cookie_store.cc
index eb41096afc782bc34fc8060956781348fb6f10f1..c802bd5a2856b1f6c5ba7226204601f987f6f80e 100644
--- a/chrome/browser/prerender/prerender_cookie_store.cc
+++ b/chrome/browser/prerender/prerender_cookie_store.cc
@@ -233,6 +233,16 @@ void PrerenderCookieStore::OnCookieChangedForURL(
   }
 }
 
+scoped_ptr<CookieStore::CookieChangedSubscription>
+PrerenderCookieStore::AddCallbackForCookie(
+    const GURL& url,
+    const std::string& name,
+    const CookieChangedCallback& callback) {
+  // Unimplemented.
+  // TODO(ellyjones): implement?

[erikwright (departed), 2014/10/24 20:11:10]

use "NOTIMPLEMENTED();" from base/logging.h so that we catch any unexpected
usage of this.

+  return scoped_ptr<CookieChangedSubscription>();
+}
+
 PrerenderCookieStore::CookieOperation::CookieOperation() {
 }