[heap] Move IdentityMap data structure out of heap.

test/cctest/test-identity-map.cc

 // Copyright 2015 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.
 
 #include "src/v8.h"
 
-#include "src/heap/identity-map.h"
+#include "src/identity-map.h"
 #include "src/zone.h"
 
 #include "test/cctest/cctest.h"
 
 namespace v8 {
 namespace internal {
 
 // Helper for testing. A "friend" of the IdentityMapBase class, it is able to
 // "move" objects to simulate GC for testing the internals of the map.
 class IdentityMapTester : public HandleAndZoneScope {
@@ skipping 312 matching lines @@
   t.heap()->CollectGarbage(i::NEW_SPACE);
 
   // Check that searching for the numbers finds the same values.
   for (size_t i = 0; i < arraysize(num_keys); i++) {
     t.CheckFind(num_keys[i], &num_keys[i]);
     t.CheckGet(num_keys[i], &num_keys[i]);
   }
 }
 }
 }