Update {virtual,override,final} to follow C++11 style in chrome/browser/chromeos/drive.

chrome/browser/chromeos/drive/file_cache_unittest.cc

Index: chrome/browser/chromeos/drive/file_cache_unittest.cc
diff --git a/chrome/browser/chromeos/drive/file_cache_unittest.cc b/chrome/browser/chromeos/drive/file_cache_unittest.cc
index 10c0bafafc3b6d030f1047e46e7b10922c341ac4..4d0299965f6878e372226dba6a00e03097c6c076 100644
--- a/chrome/browser/chromeos/drive/file_cache_unittest.cc
+++ b/chrome/browser/chromeos/drive/file_cache_unittest.cc
@@ -33,7 +33,7 @@ const char kCacheFileDirectory[] = "files";
 // Tests FileCache methods working with the blocking task runner.
 class FileCacheTest : public testing::Test {
  protected:
-  virtual void SetUp() override {
+  void SetUp() override {
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
     const base::FilePath metadata_dir = temp_dir_.path().AppendASCII("meta");
     cache_files_dir_ = temp_dir_.path().AppendASCII(kCacheFileDirectory);