Add asserts to try to flush out test flakiness.

test/mjsunit/elements-kind.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 129 matching lines @@
 assertKind(elements_kind.external_short,          new Int16Array(666));
 assertKind(elements_kind.external_unsigned_short, new Uint16Array(42));
 assertKind(elements_kind.external_int,            new Int32Array(0xF));
 assertKind(elements_kind.external_unsigned_int,   new Uint32Array(23));
 assertKind(elements_kind.external_float,          new Float32Array(7));
 assertKind(elements_kind.external_double,         new Float64Array(0));
 assertKind(elements_kind.external_pixel,          new PixelArray(512));
 
 // Crankshaft support for smi-only array elements.
 function monomorphic(array) {
+  assertKind(elements_kind.fast_smi_only, array);
   for (var i = 0; i < 3; i++) {
     array[i] = i + 10;
   }
   assertKind(elements_kind.fast_smi_only, array);
   for (var i = 0; i < 3; i++) {
     var a = array[i];
     assertEquals(i + 10, a);
   }
 }
 var smi_only = new Array(1, 2, 3);
+assertKind(elements_kind.fast_smi_only, smi_only);
 for (var i = 0; i < 3; i++) monomorphic(smi_only);
 %OptimizeFunctionOnNextCall(monomorphic);
 monomorphic(smi_only);
 
 if (support_smi_only_arrays) {
   function construct_smis() {
     var a = [0, 0, 0];
     a[0] = 0;  // Send the COW array map to the steak house.
     assertKind(elements_kind.fast_smi_only, a);
     return a;
@@ skipping 165 matching lines @@
   var a = ["foo", "bar"];
   assertKind(elements_kind.fast, a);
   var b = a.splice(0, 1);
   assertKind(elements_kind.fast, b);
   var c = a.slice(0, 1);
   assertKind(elements_kind.fast, c);
 }
 
 // Throw away type information in the ICs for next stress run.
 gc();