JS: Emit variables for 'this'

The extractor does not emit bindings for 'this', we just ensure that a variable exists for it

Author: asgerf

javascript/extractor/src/com/semmle/js/extractor/ASTExtractor.java

@@ -819,6 +819,7 @@ public Label visit(Program nd, Context c) {
       // add all declared global (or module-scoped) names, both non-lexical and lexical
       scopeManager.addNames(scopeManager.collectDeclaredNames(nd, isStrict, false, DeclKind.none));
       scopeManager.addNames(scopeManager.collectDeclaredNames(nd, isStrict, true, DeclKind.none));
+      scopeManager.addVariables("this");
 
       visitAll(nd.getBody(), toplevelLabel);
 
@@ -1070,6 +1071,9 @@ private void extractFunction(IFunction nd, Label key) {
 
       scopeManager.enterScope((Node) nd);
       scopeManager.addNames(locals);
+      if (!(nd instanceof ArrowFunctionExpression)) {
+        scopeManager.addVariables("this");
+      }
 
       // The name of a function expression binds to its own scope.
       if (nd.getId() != null && nd instanceof AFunctionExpression) {