Remove stale include of cancelable_request.h.

chrome/browser/favicon/favicon_service.h

Index: chrome/browser/favicon/favicon_service.h
diff --git a/chrome/browser/favicon/favicon_service.h b/chrome/browser/favicon/favicon_service.h
index 565147ed57e6d5ec84a95a21f56e971ed724eb50..2c4f805f598d1c8fcc015364d06fd2b1c0cf0f55 100644
--- a/chrome/browser/favicon/favicon_service.h
+++ b/chrome/browser/favicon/favicon_service.h
@@ -11,7 +11,6 @@
 #include "base/containers/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/task/cancelable_task_tracker.h"
-#include "chrome/browser/common/cancelable_request.h"
 #include "chrome/common/favicon/favicon_types.h"
 #include "chrome/common/ref_counted_util.h"
 #include "components/keyed_service/core/keyed_service.h"
@@ -28,10 +27,7 @@ struct FaviconImageResult;
 
 // The favicon service provides methods to access favicons. It calls the history
 // backend behind the scenes.
-//
-// This service is thread safe. Each request callback is invoked in the
-// thread that made the request.
-class FaviconService : public CancelableRequestProvider, public KeyedService {
+class FaviconService : public KeyedService {
  public:
   explicit FaviconService(Profile* profile);