Fixing default typeRoots on Windows

Without this function ignores "\"

Author: flekmatik

src/compiler/moduleNameResolver.ts

@@ -144,7 +144,7 @@ namespace ts {
         }
 
         let typeRoots: string[];
-        forEachAncestorDirectory(currentDirectory, directory => {
+        forEachAncestorDirectory(ts.normalizePath(currentDirectory), directory => {
             const atTypes = combinePaths(directory, nodeModulesAtTypes);
             if (host.directoryExists(atTypes)) {
                 (typeRoots || (typeRoots = [])).push(atTypes);
@@ -1056,4 +1056,4 @@ namespace ts {
             directory = parentPath;
         }
     }
-}
+}