Don't skip markLinkedReferences on ambients

Author: jakebailey

src/compiler/checker.ts

@@ -29679,9 +29679,6 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         if (!canCollectSymbolAliasAccessabilityData) {
             return;
         }
-        if (location.flags & NodeFlags.Ambient) {
-            return; // References within types and declaration files are never going to contribute to retaining a JS import
-        }
         switch (hint) {
             case ReferenceHint.Identifier:
                 return markIdentifierAliasReferenced(location as Identifier);

tests/baselines/reference/decoratorMetadataElidedImportOnDeclare(module=commonjs).js

@@ -26,6 +26,7 @@ var __metadata = (this && this.__metadata) || function (k, v) {
     if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
 };
 Object.defineProperty(exports, "__esModule", { value: true });
+const observable_1 = require("./observable");
 function whatever(a, b) { }
 class Test {
 }

tests/baselines/reference/decoratorMetadataElidedImportOnDeclare(module=esnext).js

@@ -24,11 +24,11 @@ var __decorate = (this && this.__decorate) || function (decorators, target, key,
 var __metadata = (this && this.__metadata) || function (k, v) {
     if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
 };
+import { Observable } from './observable';
 function whatever(a, b) { }
 class Test {
 }
 __decorate([
     whatever,
     __metadata("design:type", Observable)
 ], Test.prototype, "prop", void 0);
-export {};

tests/baselines/reference/importDeclWithDeclareModifier.errors.txt

@@ -1,15 +1,18 @@
 importDeclWithDeclareModifier.ts(5,9): error TS1029: 'export' modifier must precede 'declare' modifier.
+importDeclWithDeclareModifier.ts(5,27): error TS2708: Cannot use namespace 'x' as a value.
 importDeclWithDeclareModifier.ts(5,29): error TS2694: Namespace 'x' has no exported member 'c'.
 
 
-==== importDeclWithDeclareModifier.ts (2 errors) ====
+==== importDeclWithDeclareModifier.ts (3 errors) ====
     module x {
         interface c {
         }
     }
     declare export import a = x.c;
             ~~~~~~
 !!! error TS1029: 'export' modifier must precede 'declare' modifier.
+                              ~
+!!! error TS2708: Cannot use namespace 'x' as a value.
                                 ~
 !!! error TS2694: Namespace 'x' has no exported member 'c'.
     var b: a;

tests/baselines/reference/importDeclWithDeclareModifier.js

@@ -15,16 +15,3 @@ Object.defineProperty(exports, "__esModule", { value: true });
 exports.a = void 0;
 exports.a = x.c;
 var b;
-
-
-!!!! File importDeclWithDeclareModifier.js differs from original emit in noCheck emit
-//// [importDeclWithDeclareModifier.js]
-===================================================================
---- Expected	The full check baseline
-+++ Actual	with noCheck set
-@@ -1,5 +1,3 @@
- "use strict";
- Object.defineProperty(exports, "__esModule", { value: true });
--exports.a = void 0;
--exports.a = x.c;
- var b;

tests/baselines/reference/reexportedMissingAlias.errors.txt

@@ -1,9 +1,12 @@
+second.d.ts(1,27): error TS2304: Cannot find name 'CompletelyMissing'.
 second.d.ts(1,27): error TS2503: Cannot find namespace 'CompletelyMissing'.
 
 
-==== second.d.ts (1 errors) ====
+==== second.d.ts (2 errors) ====
     export import Component = CompletelyMissing;
                               ~~~~~~~~~~~~~~~~~
+!!! error TS2304: Cannot find name 'CompletelyMissing'.
+                              ~~~~~~~~~~~~~~~~~
 !!! error TS2503: Cannot find namespace 'CompletelyMissing'.
 ==== first.d.ts (0 errors) ====
     import * as Second from './second';