base: Remove some unnecessary const scoped_refptr<>&.

base/files/important_file_writer.h

Index: base/files/important_file_writer.h
diff --git a/base/files/important_file_writer.h b/base/files/important_file_writer.h
index 1b2ad5caed07a3da5dfccf456ca447a88a614bd7..4d18c0bd2e0ce923773fc8cacd4b4731dd43b6f5 100644
--- a/base/files/important_file_writer.h
+++ b/base/files/important_file_writer.h
@@ -63,11 +63,11 @@ class BASE_EXPORT ImportantFileWriter : public NonThreadSafe {
   // execute file I/O operations.
   // All non-const methods, ctor and dtor must be called on the same thread.
   ImportantFileWriter(const FilePath& path,
-                      const scoped_refptr<SequencedTaskRunner>& task_runner);
+                      scoped_refptr<SequencedTaskRunner> task_runner);
 
   // Same as above, but with a custom commit interval.
   ImportantFileWriter(const FilePath& path,
-                      const scoped_refptr<SequencedTaskRunner>& task_runner,
+                      scoped_refptr<SequencedTaskRunner> task_runner,
                       TimeDelta interval);
 
   // You have to ensure that there are no pending writes at the moment