FileAPI: Clean up around FileSystemBackend

webkit/browser/fileapi/sandbox_file_system_backend.cc

Index: webkit/browser/fileapi/sandbox_file_system_backend.cc
diff --git a/webkit/browser/fileapi/sandbox_file_system_backend.cc b/webkit/browser/fileapi/sandbox_file_system_backend.cc
index 12f0705de396264470670ffc96120c8160c73623..5b3301f83e123561374d6f1efe189c6e3437d2d5 100644
--- a/webkit/browser/fileapi/sandbox_file_system_backend.cc
+++ b/webkit/browser/fileapi/sandbox_file_system_backend.cc
@@ -94,11 +94,11 @@ class ObfuscatedOriginEnumerator
 };
 
 void DidOpenFileSystem(
-    base::WeakPtr<SandboxFileSystemBackend> mount_point_provider,
+    base::WeakPtr<SandboxFileSystemBackend> sandbox_backend,
     const base::Callback<void(base::PlatformFileError error)>& callback,
     base::PlatformFileError* error) {
-  if (mount_point_provider.get())
-    mount_point_provider.get()->CollectOpenFileSystemMetrics(*error);
+  if (sandbox_backend.get())
+    sandbox_backend.get()->CollectOpenFileSystemMetrics(*error);
   callback.Run(*error);
 }