Fix async/generator scope tests

FIX: Fix a bug where a class field initialized to an async arrow function wouldn't
allow await inside it. Same issue existed for generator arrow functions with yield.

Issue #1030

Author: marijnh

acorn/src/state.js

@@ -97,8 +97,8 @@ export class Parser {
   }
 
   get inFunction() { return (this.currentVarScope().flags & SCOPE_FUNCTION) > 0 }
-  get inGenerator() { return (this.currentVarScope().flags & SCOPE_GENERATOR) > 0 && !this.currentThisScope().inClassFieldInit }
-  get inAsync() { return (this.currentVarScope().flags & SCOPE_ASYNC) > 0 && !this.currentThisScope().inClassFieldInit }
+  get inGenerator() { return (this.currentVarScope().flags & SCOPE_GENERATOR) > 0 && !this.currentVarScope().inClassFieldInit }
+  get inAsync() { return (this.currentVarScope().flags & SCOPE_ASYNC) > 0 && !this.currentVarScope().inClassFieldInit }
   get allowSuper() {
     const {flags, inClassFieldInit} = this.currentThisScope()
     return (flags & SCOPE_SUPER) > 0 || inClassFieldInit