Refactor project references and source map tsserver tests so they are inline for easy editing (microsoft#42782)

Author: sheetalkamat

src/harness/virtualFileSystemWithWatch.ts

@@ -195,7 +195,7 @@ interface Array<T> { length: number; [n: number]: T; }`
         checkMap(caption, arrayToMap(actual, identity), expected, /*eachKeyCount*/ undefined);
     }
 
-    export function checkWatchedFiles(host: TestServerHost, expectedFiles: string[], additionalInfo?: string) {
+    export function checkWatchedFiles(host: TestServerHost, expectedFiles: readonly string[], additionalInfo?: string) {
         checkMap(`watchedFiles:: ${additionalInfo || ""}::`, host.watchedFiles, expectedFiles, /*eachKeyCount*/ undefined);
     }
 

src/testRunner/tsconfig.json

@@ -189,6 +189,7 @@
         "unittests/tsserver/projectReferenceCompileOnSave.ts",
         "unittests/tsserver/projectReferenceErrors.ts",
         "unittests/tsserver/projectReferences.ts",
+        "unittests/tsserver/projectReferencesSourcemap.ts",
         "unittests/tsserver/projects.ts",
         "unittests/tsserver/refactors.ts",
         "unittests/tsserver/reload.ts",