Delete some unused code found by -Wunused-function

chrome/browser/value_store/value_store_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.
 
 #include "chrome/browser/value_store/value_store_unittest.h"
 
 #include "base/json/json_writer.h"
 #include "base/file_util.h"
 #include "base/values.h"
 
 using content::BrowserThread;
 
 namespace {
 
 // To save typing ValueStore::DEFAULTS everywhere.
 const ValueStore::WriteOptions DEFAULTS = ValueStore::DEFAULTS;
 
 // Gets the pretty-printed JSON for a value.
 std::string GetJSON(const Value& value) {
   std::string json;
   base::JSONWriter::WriteWithOptions(&value,
                                      base::JSONWriter::OPTIONS_PRETTY_PRINT,
                                      &json);
   return json;
 }
 
-// Pretty-prints a set of strings.
-std::string ToString(const std::set<std::string>& strings) {
-  std::string string("{");
-  for (std::set<std::string>::const_iterator it = strings.begin();
-      it != strings.end(); ++it) {
-    if (it != strings.begin()) {
-      string.append(", ");
-    }
-    string.append(*it);
-  }
-  string.append("}");
-  return string;
-}
-
 }  // namespace
 
 // Compares two possibly NULL values for equality, filling |error| with an
 // appropriate error message if they're different.
 bool ValuesEqual(
     const Value* expected, const Value* actual, std::string* error) {
   if (expected == actual) {
     return true;
   }
   if (expected && !actual) {
@@ skipping 434 matching lines @@
   }
   {
     ValueStoreChangeList changes;
     changes.push_back(ValueStoreChange(key3_, val3_->DeepCopy(), NULL));
     changes.push_back(
         ValueStoreChange("qwerty", val3_->DeepCopy(), NULL));
     EXPECT_PRED_FORMAT2(ChangesEq, changes, storage_->Clear());
     EXPECT_PRED_FORMAT2(ChangesEq, ValueStoreChangeList(), storage_->Clear());
   }
 }