Standardize usage of virtual/override/final in content/browser/

content/browser/indexed_db/indexed_db_transaction.cc

Index: content/browser/indexed_db/indexed_db_transaction.cc
diff --git a/content/browser/indexed_db/indexed_db_transaction.cc b/content/browser/indexed_db/indexed_db_transaction.cc
index d2fc75f5117d704780097105623bf93269e9aac0..6609e02499b5da961c7d6e7c319aa0cf334df68f 100644
--- a/content/browser/indexed_db/indexed_db_transaction.cc
+++ b/content/browser/indexed_db/indexed_db_transaction.cc
@@ -212,12 +212,12 @@ class BlobWriteCallbackImpl : public IndexedDBBackingStore::BlobWriteCallback {
   explicit BlobWriteCallbackImpl(
       scoped_refptr<IndexedDBTransaction> transaction)
       : transaction_(transaction) {}
-  virtual void Run(bool succeeded) override {
+  void Run(bool succeeded) override {
     transaction_->BlobWriteComplete(succeeded);
   }
 
  protected:
-  virtual ~BlobWriteCallbackImpl() {}
+  ~BlobWriteCallbackImpl() override {}
 
  private:
   scoped_refptr<IndexedDBTransaction> transaction_;