Address PR comments

1. Test name.originalKeywordKind: SyntaxKind instead of name.text: string.
2. Revert regression in comment placement when emitting methods as function properties.

src/compiler/binder.ts

@@ -2267,8 +2267,8 @@ namespace ts {
             transformFlags |= TransformFlags.AssertTypeScript;
         }
 
-        // If the parameter's name is 'this, then it is TypeScript syntax.
-        if ((node.name as Identifier).text === "this") {
+        // If the parameter's name is 'this', then it is TypeScript syntax.
+        if (node.name && (node.name as Identifier).originalKeywordKind === SyntaxKind.ThisKeyword) {
             transformFlags |= TransformFlags.AssertTypeScript;
         }
 

src/compiler/transformers/ts.ts

@@ -2115,12 +2115,12 @@ namespace ts {
          * This function will be called when one of the following conditions are met:
          * - The node has an accessibility modifier.
          * - The node has a questionToken.
-         * - The node's text is "this".
+         * - The node's kind is ThisKeyword.
          *
          * @param node The parameter declaration node.
          */
         function visitParameter(node: ParameterDeclaration) {
-            if ((node.name as Identifier).text === "this") {
+            if (node.name && (node.name as Identifier).originalKeywordKind === SyntaxKind.ThisKeyword) {
                 return undefined;
             }
             const clone = getMutableClone(node);

tests/baselines/reference/thisTypeInFunctions.js

@@ -243,8 +243,7 @@ function implicitThis(n) {
 var impl = {
     a: 12,
     explicitVoid2: function () { return _this.a; },
-    explicitVoid1: // ok, this: any because it refers to some outer object (window?)
-    function () { return 12; },
+    explicitVoid1: function () { return 12; },
     explicitStructural: function () {
         return this.a;
     },