Delete some unused code found by -Wunused-function

sync/internal_api/sync_manager_impl_unittest.cc

 // Copyright (c) 2012 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.
 
 // Unit tests for the SyncApi. Note that a lot of the underlying
 // functionality is provided by the Syncable layer, which has its own
 // unit tests. We'll test SyncApi specific things in this harness.
 
 #include <cstddef>
 #include <map>
@@ skipping 76 matching lines @@
 using syncable::IS_DEL;
 using syncable::IS_UNSYNCED;
 using syncable::kEncryptedString;
 using syncable::NON_UNIQUE_NAME;
 using syncable::SPECIFICS;
 
 namespace {
 
 const char kTestChromeVersion[] = "test chrome version";
 
-void DoNothing() {}
-
 void ExpectInt64Value(int64 expected_value,
                       const DictionaryValue& value, const std::string& key) {
   std::string int64_str;
   EXPECT_TRUE(value.GetString(key, &int64_str));
   int64 val = 0;
   EXPECT_TRUE(base::StringToInt64(int64_str, &val));
   EXPECT_EQ(expected_value, val);
 }
 
 void ExpectTimeValue(const base::Time& expected_value,
@@ skipping 2775 matching lines @@
 
   // Verify only the non-disabled types remain after cleanup.
   sync_manager_.PurgeDisabledTypes(enabled_types, new_enabled_types);
   EXPECT_TRUE(new_enabled_types.Equals(
       Union(sync_manager_.InitialSyncEndedTypes(), partial_enabled_types)));
   EXPECT_TRUE(disabled_types.Equals(
       sync_manager_.GetTypesWithEmptyProgressMarkerToken(ModelTypeSet::All())));
 }
 
 }  // namespace