fixup! fixup! src: make BuiltinLoader threadsafe and non-global

Author: addaleax

Diff for: src/node.cc

@@ -126,8 +126,6 @@
 
 namespace node {
 
-using builtins::BuiltinLoader;
-
 using v8::EscapableHandleScope;
 using v8::Isolate;
 using v8::Local;

Diff for: src/node_realm.cc

@@ -8,7 +8,6 @@
 
 namespace node {
 
-using builtins::BuiltinLoader;
 using v8::Context;
 using v8::EscapableHandleScope;
 using v8::Function;

Diff for: src/node_threadsafe_cow.h

@@ -80,8 +80,8 @@ class ThreadsafeCopyOnWrite final {
 
  private:
   struct Impl {
-    Impl(const T& data) : data(data) {}
-    Impl(T&& data) : data(std::move(data)) {}
+    explicit Impl(const T& data) : data(data) {}
+    explicit Impl(T&& data) : data(std::move(data)) {}
 
     Impl(const Impl& other);
     Impl& operator=(const Impl& other) = delete;