Fix typo

Author: mhegazy

src/compiler/program.ts

@@ -494,13 +494,13 @@ module ts {
  return getNormalizedPathFromPathComponents(commonPathComponents);
  }
 
- function checkSourceFilesBelongToPath(soruceFiles: SourceFile[], rootDirectory: string): boolean {
+ function checkSourceFilesBelongToPath(sourceFiles: SourceFile[], rootDirectory: string): boolean {
  let allFilesBelongToPath = true;
- if (soruceFiles) {
+ if (sourceFiles) {
  let currentDirectory = host.getCurrentDirectory();
  let absoluteRootDirectoryPath = host.getCanonicalFileName(getNormalizedAbsolutePath(rootDirectory, currentDirectory));
 
- for (var sourceFile of soruceFiles) {
+ for (var sourceFile of sourceFiles) {
  if (!isDeclarationFile(sourceFile)) {
  let absoluteSourceFilePath = host.getCanonicalFileName(getNormalizedAbsolutePath(sourceFile.fileName, currentDirectory));
  if (absoluteSourceFilePath.indexOf(absoluteRootDirectoryPath) !== 0) {