base: Get rid of 'using' declaration of StringAppendF.

net/http/http_cache_unittest.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/http_cache.h"
 
 #include "base/hash_tables.h"
 #include "base/message_loop.h"
 #include "base/scoped_vector.h"
 #include "base/string_util.h"
@@ skipping 886 matching lines @@
 
   EXPECT_LT(end, 80);
 
   std::string content_range = base::StringPrintf(
       "Content-Range: bytes %d-%d/80\n", start, end);
   response_headers->append(content_range);
 
   if (!request->extra_headers.HasHeader("If-None-Match") || modified_) {
     EXPECT_EQ(9, (end - start) % 10);
     std::string data;
-    for (int block_start = start; block_start < end; block_start += 10)
-      StringAppendF(&data, "rg: %02d-%02d ", block_start, block_start + 9);
+    for (int block_start = start; block_start < end; block_start += 10) {
+      base::StringAppendF(&data, "rg: %02d-%02d ",
+                          block_start, block_start + 9);
+    }
     *response_data = data;
 
     if (end - start != 9) {
       // We also have to fix content-length.
       int len = end - start + 1;
       EXPECT_EQ(0, len % 10);
       std::string content_length = base::StringPrintf("Content-Length: %d\n",
                                                       len);
       response_headers->replace(response_headers->find("Content-Length:"),
                                 content_length.size(), content_length);
@@ skipping 3924 matching lines @@
   // Now return 200 when validating the entry so the metadata will be lost.
   MockTransaction trans2(kTypicalGET_Transaction);
   trans2.load_flags = net::LOAD_VALIDATE_CACHE;
   RunTransactionTestWithResponseInfo(cache.http_cache(), trans2, &response);
   EXPECT_TRUE(response.metadata.get() == NULL);
 
   EXPECT_EQ(3, cache.network_layer()->transaction_count());
   EXPECT_EQ(4, cache.disk_cache()->open_count());
   EXPECT_EQ(1, cache.disk_cache()->create_count());
 }