Replace uses of hash_map in //base

base/id_map_unittest.cc

 // Copyright (c) 2011 The Chromium 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 "base/id_map.h"
 
 #include <stdint.h>
 
 #include <memory>
 
@@ skipping 88 matching lines @@
 
 TEST(IDMapTest, IteratorRemainsValidWhenRemovingOtherElements) {
   IDMap<TestObject*> map;
 
   const int kCount = 5;
   TestObject obj[kCount];
 
   for (int i = 0; i < kCount; i++)
     map.Add(&obj[i]);
 
-  // IDMap uses a hash_map, which has no predictable iteration order.
+  // IDMap has no predictable iteration order.

[Łukasz Anforowicz, 2017/04/24 18:46:10]

Thanks for making the comment more generic - this is great.

nit: Do you think this comment should also be made part of the public contract
of the IDMap (e.g. by also adding an equivalent of this comment to the doc
comments of IdMap::Iterator class)?

   int32_t ids_in_iteration_order[kCount];
   const TestObject* objs_in_iteration_order[kCount];
   int counter = 0;
   for (IDMap<TestObject*>::const_iterator iter(&map); !iter.IsAtEnd();
        iter.Advance()) {
     ids_in_iteration_order[counter] = iter.GetCurrentKey();
     objs_in_iteration_order[counter] = iter.GetCurrentValue();
     counter++;
   }
 
@@ skipping 89 matching lines @@
 
 TEST(IDMapTest, IteratorRemainsValidWhenClearing) {
   IDMap<TestObject*> map;
 
   const int kCount = 5;
   TestObject obj[kCount];
 
   for (int i = 0; i < kCount; i++)
     map.Add(&obj[i]);
 
-  // IDMap uses a hash_map, which has no predictable iteration order.
+  // IDMap has no predictable iteration order.
   int32_t ids_in_iteration_order[kCount];
   const TestObject* objs_in_iteration_order[kCount];
   int counter = 0;
   for (IDMap<TestObject*>::const_iterator iter(&map); !iter.IsAtEnd();
        iter.Advance()) {
     ids_in_iteration_order[counter] = iter.GetCurrentKey();
     objs_in_iteration_order[counter] = iter.GetCurrentValue();
     counter++;
   }
 
@@ skipping 138 matching lines @@
   EXPECT_EQ(kId1, iter.GetCurrentKey());
   EXPECT_EQ(&obj1, iter.GetCurrentValue());
   iter.Advance();
   ASSERT_TRUE(iter.IsAtEnd());
 
   map.Remove(kId1);
   EXPECT_TRUE(map.IsEmpty());
 }
 
 }  // namespace