Make resolvedUsingTsExtension optional

Author: andrewbranch

Diff for: src/compiler/types.ts

@@ -7224,7 +7224,7 @@ export interface ResolvedModule {
      * True if the original module reference used a .ts extension to refer directly to a .ts file,
      * which should produce an error during checking if emit is enabled.
      */
-    resolvedUsingTsExtension: boolean;
+    resolvedUsingTsExtension?: boolean;
 }
 
 /**

Diff for: src/testRunner/unittests/moduleResolution.ts

@@ -169,7 +169,6 @@ describe("unittests:: moduleResolution:: Node module resolution - non-relative p
                 resolvedFileName: "/sub/node_modules/a/index.ts",
                 isExternalLibraryImport: true,
                 extension: ts.Extension.Ts,
-                resolvedUsingTsExtension: false,
             },
             failedLookupLocations: [],
             affectingLocations: [],
@@ -185,7 +184,6 @@ describe("unittests:: moduleResolution:: Node module resolution - non-relative p
                 resolvedFileName: "/sub/directory/node_modules/b/index.ts",
                 isExternalLibraryImport: true,
                 extension: ts.Extension.Ts,
-                resolvedUsingTsExtension: false,
             },
             failedLookupLocations: [],
             affectingLocations: [],
@@ -203,7 +201,6 @@ describe("unittests:: moduleResolution:: Node module resolution - non-relative p
                 resolvedFileName: "/bar/node_modules/c/index.ts",
                 isExternalLibraryImport: true,
                 extension: ts.Extension.Ts,
-                resolvedUsingTsExtension: false,
             },
             failedLookupLocations: [],
             affectingLocations: [],
@@ -220,7 +217,6 @@ describe("unittests:: moduleResolution:: Node module resolution - non-relative p
                 resolvedFileName: "/foo/index.ts",
                 isExternalLibraryImport: true,
                 extension: ts.Extension.Ts,
-                resolvedUsingTsExtension: false,
             },
             failedLookupLocations: [],
             affectingLocations: [],
@@ -236,7 +232,6 @@ describe("unittests:: moduleResolution:: Node module resolution - non-relative p
                 resolvedFileName: "d:/bar/node_modules/e/index.ts",
                 isExternalLibraryImport: true,
                 extension: ts.Extension.Ts,
-                resolvedUsingTsExtension: false,
             },
             failedLookupLocations: [],
             affectingLocations: [],