Move AppendFile and *CurrentDirectory to the base namespace.

gin/shell/gin_main.cc

Index: gin/shell/gin_main.cc
diff --git a/gin/shell/gin_main.cc b/gin/shell/gin_main.cc
index 3b990f059d83a081e6d3010c69f7aaf1f8ad07bd..6673b6a685ca530abaa5ef69e852982a359ab451 100644
--- a/gin/shell/gin_main.cc
+++ b/gin/shell/gin_main.cc
@@ -33,7 +33,7 @@ void Run(base::WeakPtr<Runner> runner, const base::FilePath& path) {
 
 std::vector<base::FilePath> GetModuleSearchPaths() {
   std::vector<base::FilePath> module_base(1);
-  CHECK(file_util::GetCurrentDirectory(&module_base[0]));
+  CHECK(base::GetCurrentDirectory(&module_base[0]));
   return module_base;
 }