[Extensions] Make ExtensionAPI use unique_ptrs instead of linked_ptrs

extensions/common/extension_api.cc

 // Copyright 2013 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 "extensions/common/extension_api.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <string>
@@ skipping 201 matching lines @@
 }
 
 void ExtensionAPI::LoadSchema(const std::string& name,
                               const base::StringPiece& schema) {
   std::unique_ptr<base::ListValue> schema_list(LoadSchemaList(name, schema));
   std::string schema_namespace;
   extensions::ExtensionsClient* extensions_client =
       extensions::ExtensionsClient::Get();
   DCHECK(extensions_client);
   while (!schema_list->empty()) {
-    base::DictionaryValue* schema = NULL;
+    std::unique_ptr<base::DictionaryValue> schema;
     {
-      std::unique_ptr<base::Value> value;
-      schema_list->Remove(schema_list->GetSize() - 1, &value);
-      CHECK(value.release()->GetAsDictionary(&schema));
+      std::unique_ptr<base::Value> val;
+      schema_list->Erase(schema_list->begin(), &val);
+      schema = base::DictionaryValue::From(std::move(val));
+      CHECK(schema);
     }
-
     CHECK(schema->GetString("namespace", &schema_namespace));
-    PrefixWithNamespace(schema_namespace, schema);
-    schemas_[schema_namespace] = make_linked_ptr(schema);
+    PrefixWithNamespace(schema_namespace, schema.get());
+    schemas_[schema_namespace] = std::move(schema);
     if (!extensions_client->IsAPISchemaGenerated(schema_namespace))
       CHECK_EQ(1u, unloaded_schemas_.erase(schema_namespace));
   }
 }
 
 ExtensionAPI::ExtensionAPI() : default_configuration_initialized_(false) {
 }
 
 ExtensionAPI::~ExtensionAPI() {
 }
@@ skipping 146 matching lines @@
       break;
 
     api_name_candidate = api_name_candidate.substr(0, last_dot_index);
   }
 
   *child_name = "";
   return std::string();
 }
 
 }  // namespace extensions