Allow a ParseInfo without a script for %SetCode users

test/mjsunit/shared-function-tier-up-ignition.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Flags: --mark-shared-functions-for-tier-up --allow-natives-syntax
-// Flags: --ignition-staging --no-turbo
+// Flags: --ignition-staging --turbo

[Leszek Swirski, 2017/02/15 17:09:49]

I just noticed this -- if we're fixing this to --turbo then we may as well get
rid of it entirely, there's another test for turbo IIRC

 // Flags: --crankshaft --no-always-opt
 
 // If we are always or never optimizing it is useless.
 assertFalse(isAlwaysOptimize());
 assertFalse(isNeverOptimize());
 
 (function() {
   var sum = 0;
   var i = 0;
   for (var i = 0; i < 5; ++i) {
     var f = function(x) {
       return 2 * x;
     }
     sum += f(i);
 
     if (i == 1) {
       // f must be interpreted code.
       assertTrue(isInterpreted(f));
 
-      // Allow it to run twice (i = 0, 1), then tier-up to baseline.
-      %BaselineFunctionOnNextCall(f);
-    } else if (i == 2) {
-      // Tier-up at i = 2 should only go up to baseline.
-      assertTrue(isBaselined(f));
-
-    } else if (i == 3) {
-      // Now f must be baseline code.
-      assertTrue(isBaselined(f));
-
-      // Run two more times (i = 2, 3), then tier-up to optimized.
+      // Run twice (i = 0, 1), then tier-up.
       %OptimizeFunctionOnNextCall(f);
-    } else if (i == 4) {
-      // Tier-up at i = 4 should now go up to crankshaft.
-      assertTrue(isCrankshafted(f));
+     } else if (i == 2) {
+      // Tier-up at i = 2 should now go up to crankshaft.
+      assertTrue(isTurboFanned(f));
     }
   }
 })()