Update the streams interfaces

tests/standalone/src/FileInputStreamTest.dart

Index: tests/standalone/src/FileInputStreamTest.dart
diff --git a/tests/standalone/src/FileInputStreamTest.dart b/tests/standalone/src/FileInputStreamTest.dart
index 240b24803a5e40044534ccfe21710d925bb86b3e..d4dde8e6d38ea26eff02a8e1b67f894dac930103 100644
--- a/tests/standalone/src/FileInputStreamTest.dart
+++ b/tests/standalone/src/FileInputStreamTest.dart
@@ -3,13 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 // Testing FileInputStream, VM-only, standalone test.
 
-
-String callbackString = null;
-
-callback(List<int> buffer) {
-  callbackString =  new String.fromCharCodes(buffer);
-}
-
 // Helper method to be able to run the test from the runtime
 // directory, or the top directory.
 String getFilename(String path) =>
@@ -17,23 +10,12 @@ String getFilename(String path) =>
 
 main() {
   String fName = getFilename("tests/standalone/src/readuntil_test.dat");
-  // File contains "Hello Dart, wassup!"
+  // File contains "Hello Dart\nwassup!"
   File file = new File(fName, false);
-  FileInputStream x = new FileInputStream(file);
-  x.readUntil("Dart".charCodes(), callback);
-  file.close();
-  Expect.stringEquals("Hello Dart", callbackString);
-
-  callbackString = null;
-  file = new File(fName, false);
-  x = new FileInputStream(file);
-  x.readUntil("Darty".charCodes(), callback);
-  file.close();
-  Expect.isNull(callbackString);
-
-  file = new File(fName, false);
-  x = new FileInputStream(file);
-  x.readUntil("wassup!".charCodes(), callback);
+  StringInputStream x = new StringInputStream(file.inputStream);
+  String line = x.readLine();
+  Expect.equals("Hello Dart", line);
   file.close();
-  Expect.stringEquals("Hello Dart, wassup!", callbackString);
+  line = x.readLine();
+  Expect.equals("wassup!", line);
 }