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

tests/compiler/dart2js/cps_ir/expected/constructor_6.js

Index: tests/compiler/dart2js/cps_ir/expected/constructor_6.js
diff --git a/tests/compiler/dart2js/cps_ir/expected/constructor_6.js b/tests/compiler/dart2js/cps_ir/expected/constructor_6.js
new file mode 100644
index 0000000000000000000000000000000000000000..66d5ae513de6de6add0e06dc85f4e8fb8f74cee7
--- /dev/null
+++ b/tests/compiler/dart2js/cps_ir/expected/constructor_6.js
@@ -0,0 +1,24 @@
+// Expectation for test: 
+// class Bar {
+//   Bar(x, {y, z: 'z', w: '_', q}) {
+//     print(x);
+//     print(y);
+//     print(z);
+//     print(w);
+//     print(q);
+//   }
+// }
+// class Foo extends Bar {
+//   Foo() : super('x', y: 'y', w: 'w');
+// }
+// main() {
+//   new Foo();
+// }
+
+function() {
+  P.print("x");
+  P.print("y");
+  P.print("z");
+  P.print("w");
+  P.print(null);
+}