libaddressinput - reduce number of copies in storage class by 2

third_party/libaddressinput/chromium/chrome_storage_impl.cc

 // Copyright 2014 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 "third_party/libaddressinput/chromium/chrome_storage_impl.h"
 
 #include "base/prefs/writeable_pref_store.h"
 #include "base/values.h"
 
 namespace autofill {
 
 ChromeStorageImpl::ChromeStorageImpl(WriteablePrefStore* store)
     : backing_store_(store),
       scoped_observer_(this) {
   scoped_observer_.Add(backing_store_);
 }
 
 ChromeStorageImpl::~ChromeStorageImpl() {}
 
-void ChromeStorageImpl::Put(const std::string& key, const std::string& data) {
-  backing_store_->SetValue(key, new base::StringValue(data));
+void ChromeStorageImpl::Put(const std::string& key,
+                            scoped_ptr<std::string> data) {
+  scoped_ptr<base::StringValue> string_value(
+      new base::StringValue(std::string()));
+  string_value->GetString()->swap(*data);
+  backing_store_->SetValue(key, string_value.release());
 }
 
 void ChromeStorageImpl::Get(
     const std::string& key,
     scoped_ptr<Storage::Callback> data_ready) const {
   // |Get()| should not be const, so this is just a thunk that fixes that.
   const_cast<ChromeStorageImpl*>(this)->DoGet(key, data_ready.Pass());
 }
 
 void ChromeStorageImpl::OnPrefValueChanged(const std::string& key) {}
@@ skipping 11 matching lines @@
 void ChromeStorageImpl::DoGet(
     const std::string& key,
     scoped_ptr<Storage::Callback> data_ready) {
   if (!backing_store_->IsInitializationComplete()) {
     outstanding_requests_.push_back(
         new Request(key, data_ready.Pass()));
     return;
   }
 
   const base::Value* value;
-  std::string result;
+  const base::StringValue* string_value;
   if (backing_store_->GetValue(key, &value) &&
-      value->GetAsString(&result)) {
-    (*data_ready)(true, key, result);
+      value->GetAsString(&string_value)) {
+    (*data_ready)(true, key, string_value->GetString());
   } else {
     (*data_ready)(false, key, std::string());
   }
 }
 
 ChromeStorageImpl::Request::Request(const std::string& key,
                                     scoped_ptr<Storage::Callback> callback)
     : key(key),
       callback(callback.Pass()) {}
 
 }  // namespace autofill