testsuite updated to reflect recent changes in codegen: branch support

backend.native/tests/codegen/branching/when_through.kt

@@ -0,0 +1,10 @@
+fun when_through(i: Int): Int {
+  var value = 1
+  when (i) {
+    10 -> value = 42
+    11 -> value = 43
+    12 -> value = 44
+  }
+
+  return value
+}