Extract permission alias info from PermissionsProvider

extensions/common/api_alias_info.cc

Index: extensions/common/api_alias_info.cc
diff --git a/extensions/common/api_alias_info.cc b/extensions/common/api_alias_info.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e215703aa7b2f37d4460419454416c61fb97bf10
--- /dev/null
+++ b/extensions/common/api_alias_info.cc
@@ -0,0 +1,33 @@
+// Copyright 2016 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/api_alias_info.h"
+
+#include "extensions/common/alias.h"
+#include "extensions/common/alias_provider.h"
+
+namespace extensions {
+
+namespace {
+
+static base::LazyInstance<ApiAliasInfo> g_api_alias_info =
+    LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+// static
+ApiAliasInfo* ApiAliasInfo::GetInstance() {
+  return g_api_alias_info.Pointer();
+}
+
+void ApiAliasInfo::AddProvider(const AliasProvider& provider) {
+  std::vector<Alias> api_aliases = provider.GetValidApiAliases();
+  api_aliases_.insert(api_aliases_.end(), api_aliases.begin(),
+                      api_aliases.end());
+}
+
+ApiAliasInfo::ApiAliasInfo() {}
+ApiAliasInfo::~ApiAliasInfo() {}
+
+}  // namespace extensions