Split js_backend_cps_ir tests into multiple test units.

tests/compiler/dart2js/js_backend_cps_ir_operators_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 operators.
 
 library operators_tests;
 
-import 'js_backend_cps_ir_test.dart';
+import 'js_backend_cps_ir.dart';
 
 const List<TestEntry> tests = const [
   const TestEntry("main() { return true ? 42 : 'foo'; }"),
   const TestEntry("""
 foo() => foo();
 main() {
   print(foo() ? "hello world" : "bad bad");
 }""",
 """function() {
   P.print(P.identical(V.foo(), true) ? "hello world" : "bad bad");
@@ skipping 16 matching lines @@
   return null;
 }"""),
   const TestEntry("""
 get foo => foo;
 main() { print(foo || foo); }""",
 """function() {
   P.print(P.identical(V.foo(), true) || P.identical(V.foo(), true));
   return null;
 }"""),
 ];
+
+void main() {
+  runTests(tests);
+}