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

tests/compiler/dart2js/cps_ir/expected/basic_10.js

+// Expectation for test: 
+// main() {
+//   print(new DateTime.now().isBefore(new DateTime.now()));
+// }
+
+function() {
+  var v0 = Date.now() < Date.now(), line = v0 ? "true" : false === v0 ? "false" : String(v0);
+  if (typeof dartPrint == "function")
+    dartPrint(line);
+  else if (typeof console == "object" && typeof console.log != "undefined")
+    console.log(line);
+  else if (!(typeof window == "object")) {
+    if (!(typeof print == "function"))
+      throw "Unable to print message: " + String(line);
+    print(line);
+  }
+}