cpsir unittests: move all unittests into individual files and test runners.

tests/compiler/dart2js/cps_ir/input/runtime_types_4.dart

Index: tests/compiler/dart2js/cps_ir/input/runtime_types_4.dart
diff --git a/tests/compiler/dart2js/cps_ir/input/runtime_types_4.dart b/tests/compiler/dart2js/cps_ir/input/runtime_types_4.dart
new file mode 100644
index 0000000000000000000000000000000000000000..f45e59c458594f3c2295cf1fd1a246bd97443028
--- /dev/null
+++ b/tests/compiler/dart2js/cps_ir/input/runtime_types_4.dart
@@ -0,0 +1,7 @@
+// Method to test: generative_constructor(C#)
+class C<X, Y, Z> {
+  foo() => 'C<$X $Y, $Z>';
+}
+main() {
+  new C<C, int, String>().foo();
+}