Unset weak status of compiled scripts from Node

Compiled scripts from Node were set to weak, which caused the script
object in V8 being GCed shortly. Hence links of the script shown in
console of DevTools become invalid after GC.

Fixed nwjs/nw.js#4269

Author: Cong Liu

src/node_contextify.cc

@@ -792,6 +792,10 @@ class ContextifyScript : public BaseObject {
   ContextifyScript(Environment* env, Local<Object> object)
       : BaseObject(env, object) {
     MakeWeak<ContextifyScript>(this);
+    // Unset weak of compiled script to survival from GC for Node modules.
+    // Otherwise the links from console will be invalid shortly.
+    // See https://github.com/nwjs/nw.js/issues/4269
+    ClearWeak();
   }