debugger: assign Environment to DebugContext too

fix nodejs#7517

src/node.cc

@@ -3093,6 +3093,9 @@ static void EnableDebug(Isolate* isolate, bool wait_connect) {
   if (env == NULL)
     return;  // Still starting up.
 
+  // Assign environment to the debugger's context
+  env->AssignToContext(v8::Debug::GetDebugContext());
+
   Context::Scope context_scope(env->context());
   Local<Object> message = Object::New(env->isolate());
   message->Set(FIXED_ONE_BYTE_STRING(env->isolate(), "cmd"),
@@ -3594,6 +3597,11 @@ int Start(int argc, char** argv) {
     Locker locker(node_isolate);
     Environment* env =
         CreateEnvironment(node_isolate, argc, argv, exec_argc, exec_argv);
+    // Assign env to the debugger's context
+    if (debugger_running) {
+      HandleScope scope(env->isolate());
+      env->AssignToContext(v8::Debug::GetDebugContext());
+    }
     // This Context::Scope is here so EnableDebug() can look up the current
     // environment with Environment::GetCurrentChecked().
     // TODO(bnoordhuis) Reorder the debugger initialization logic so it can

test/debugger/test-debugger-repl.js

@@ -74,4 +74,13 @@ addTest('c', [
   /\d/, /\d/, /\d/, /\d/, /\d/
 ]);
 
-addTest('quit', []);
+// REPL and process.env regression
+addTest('repl', [
+  /Ctrl/
+]);
+
+addTest('for (var i in process.env) delete process.env[i]', []);
+
+addTest('process.env', [
+  /\{\}/
+]);