Fix TestHeapEntryIdsAndGC test. The assert was wrong.

src/profile-generator.cc

 // Copyright 2010 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 1515 matching lines @@
     uint64_t existing = FindEntry(addr);
     if (existing != 0) return existing;
   }
   uint64_t id = next_id_++;
   AddEntry(addr, id);
   return id;
 }
 
 
 void HeapObjectsMap::MoveObject(Address from, Address to) {
+  if (from == to) return;
   HashMap::Entry* entry = entries_map_.Lookup(from, AddressHash(from), false);
   if (entry != NULL) {
     void* value = entry->value;
     entries_map_.Remove(from, AddressHash(from));
     entry = entries_map_.Lookup(to, AddressHash(to), true);
-    ASSERT(entry->value == NULL);
+    // We can have an entry at the new location, it is OK, as GC can overwrite
+    // dead objects with alive objects being moved.
     entry->value = value;
   }
 }
 
 
 void HeapObjectsMap::AddEntry(Address addr, uint64_t id) {
   HashMap::Entry* entry = entries_map_.Lookup(addr, AddressHash(addr), true);
   ASSERT(entry->value == NULL);
   entry->value = reinterpret_cast<void*>(entries_->length());
   entries_->Add(EntryInfo(id));
@@ skipping 264 matching lines @@
     HeapEntry* entry = added_entries[i];
     if (entry->painted_reachable())
       diff->AddAddedEntry(entry);
   }
   return diff;
 }
 
 } }  // namespace v8::internal
 
 #endif  // ENABLE_LOGGING_AND_PROFILING