Split js_backend_cps_ir tests into multiple test units.

tests/compiler/dart2js/js_backend_cps_ir_interceptors_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
+// VMOptions=-DUSE_CPS_IR=true
 
 // Tests of interceptors.
 
 library interceptors_tests;
 
-import 'js_backend_cps_ir_test.dart';
+import 'js_backend_cps_ir.dart';
 
 const List<TestEntry> tests = const [
   const TestEntry("""
 main() {
   var g = 1;
 
   var x = g + 3;
   print(x);
 }""",
 r"""
 function() {
   var g, v0;
   g = 1;
   v0 = 3;
   P.print(J.getInterceptor(g).$add(g, v0));
   return null;
 }"""),
 ];
+
+
+void main() {
+  runTests(tests);
+}