Fix flaky FileFlusherTest.DuplicateRequests

chrome/browser/chromeos/base/file_flusher.h

Index: chrome/browser/chromeos/base/file_flusher.h
diff --git a/chrome/browser/chromeos/base/file_flusher.h b/chrome/browser/chromeos/base/file_flusher.h
index d33f9836b543f0352c3f2df9eef0a8437ba0a718..f22baaeb4c07167abf9e6d2984961782f991370c 100644
--- a/chrome/browser/chromeos/base/file_flusher.h
+++ b/chrome/browser/chromeos/base/file_flusher.h
@@ -38,6 +38,9 @@ class FileFlusher {
     on_flush_callback_for_test_ = on_flush_callback;
   }
 
+  void PauseForTest();
+  void ResumeForTest();
+
  private:
   // Job for the flushing requests.
   class Job;
@@ -54,6 +57,8 @@ class FileFlusher {
   // A callback for testing to be invoked when a file is flushed.
   OnFlushCallback on_flush_callback_for_test_;
 
+  bool paused_for_test_ = false;
+
   base::WeakPtrFactory<FileFlusher> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(FileFlusher);