Use rvalue reference instead of ExtensionBuilder::pass()

extensions/common/extension_builder.h

Index: extensions/common/extension_builder.h
diff --git a/extensions/common/extension_builder.h b/extensions/common/extension_builder.h
index 4b40178b9b71b790ce00bcae139e97d4850f1ec2..96c81d2b6d8735771a5ac04b92a6b3063c6a6e56 100644
--- a/extensions/common/extension_builder.h
+++ b/extensions/common/extension_builder.h
@@ -24,14 +24,14 @@ class ExtensionBuilder {
   ExtensionBuilder();
   ~ExtensionBuilder();
 
+  // Move constructor and operator=.
+  ExtensionBuilder(ExtensionBuilder&& other);
+  ExtensionBuilder& operator=(ExtensionBuilder&& other);
+
   // Can only be called once, after which it's invalid to use the builder.
   // CHECKs that the extension was created successfully.
   scoped_refptr<Extension> Build();
 
-  // Workaround to allow you to pass rvalue ExtensionBuilders by reference to
-  // other functions, e.g. UseBuilder(ExtensionBuilder().Pass())
-  ExtensionBuilder& Pass() { return *this; }
-
   // Defaults to FilePath().
   ExtensionBuilder& SetPath(const base::FilePath& path);
 
@@ -58,6 +58,8 @@ class ExtensionBuilder {
   scoped_ptr<base::DictionaryValue> manifest_;
   int flags_;
   std::string id_;
+
+  DISALLOW_COPY_AND_ASSIGN(ExtensionBuilder);
 };
 
 }  // namespace extensions