dart:io | Directory.createTemp - fix missed rename of template to prefix.

sdk/lib/io/directory.dart

Index: sdk/lib/io/directory.dart
diff --git a/sdk/lib/io/directory.dart b/sdk/lib/io/directory.dart
index 95e6aa86ce831ecf844e290ee7093a3631faccb6..dcb2992213dad1da587f29f846ad77977763abf3 100644
--- a/sdk/lib/io/directory.dart
+++ b/sdk/lib/io/directory.dart
@@ -86,7 +86,7 @@ abstract class Directory implements FileSystemEntity {
    * Returns a [:Future<Directory>:] that completes with the newly
    * created temporary directory.
    */
-  Future<Directory> createTemp([String template]);
+  Future<Directory> createTemp([String prefix]);
 
   /**
    * Synchronously creates a temporary directory in this directory.
@@ -96,7 +96,7 @@ abstract class Directory implements FileSystemEntity {
    *
    * Returns the newly created temporary directory.
    */
-  Directory createTempSync([String template]);
+  Directory createTempSync([String prefix]);
 
   Future<String> resolveSymbolicLinks();