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

tests/compiler/dart2js/cps_ir/input/constructor_1.dart

Index: tests/compiler/dart2js/cps_ir/input/constructor_1.dart
diff --git a/tests/compiler/dart2js/cps_ir/input/constructor_1.dart b/tests/compiler/dart2js/cps_ir/input/constructor_1.dart
new file mode 100644
index 0000000000000000000000000000000000000000..1cc265accae69635bd91cf7ca7852196a81ea0bd
--- /dev/null
+++ b/tests/compiler/dart2js/cps_ir/input/constructor_1.dart
@@ -0,0 +1,11 @@
+class Base {
+  var x;
+  Base(this.x);
+}
+class Sub extends Base {
+  var y;
+  Sub(x, this.y) : super(x);
+}
+main() {
+  print(new Sub(1, 2).x);
+}