Revert of components/metrics: Add runtime memory leak detector

components/metrics/leak_detector/call_stack_table.h

-// Copyright 2015 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.
-
-#ifndef COMPONENTS_METRICS_LEAK_DETECTOR_CALL_STACK_TABLE_H_
-#define COMPONENTS_METRICS_LEAK_DETECTOR_CALL_STACK_TABLE_H_
-
-#include <stdint.h>
-
-#include <functional>  // For std::equal_to.
-
-#include "base/containers/hash_tables.h"
-#include "base/macros.h"
-#include "components/metrics/leak_detector/custom_allocator.h"
-#include "components/metrics/leak_detector/leak_analyzer.h"
-#include "components/metrics/leak_detector/stl_allocator.h"
-
-namespace metrics {
-namespace leak_detector {
-
-struct CallStack;
-
-// Contains a hash table where the key is the call stack and the value is the
-// number of allocations from that call stack.
-// Not thread-safe.
-class CallStackTable {
- public:
-  struct StoredHash {
-    size_t operator()(const CallStack* call_stack) const;
-  };
-
-  explicit CallStackTable(int call_stack_suspicion_threshold);
-  ~CallStackTable();
-
-  // Add/Remove an allocation for the given call stack.
-  // Note that this class does NOT own the CallStack objects. Instead, it
-  // identifies different CallStacks by their hashes.
-  void Add(const CallStack* call_stack);
-  void Remove(const CallStack* call_stack);
-
-  // Check for leak patterns in the allocation data.
-  void TestForLeaks();
-
-  const LeakAnalyzer& leak_analyzer() const { return leak_analyzer_; }
-
-  size_t size() const { return entry_map_.size(); }
-  bool empty() const { return entry_map_.empty(); }
-
-  uint32_t num_allocs() const { return num_allocs_; }
-  uint32_t num_frees() const { return num_frees_; }
-
- private:
-  // Hash table entry used to track allocation stats for a given call stack.
-  struct Entry {
-    // Net number of allocs (allocs minus frees).
-    uint32_t net_num_allocs;
-  };
-
-  // Total number of allocs and frees in this table.
-  uint32_t num_allocs_;
-  uint32_t num_frees_;
-
-  // Hash table containing entries.
-  using TableEntryAllocator =
-      STLAllocator<std::pair<const CallStack*, Entry>, CustomAllocator>;
-  base::hash_map<const CallStack*,
-                 Entry,
-                 StoredHash,
-                 std::equal_to<const CallStack*>,
-                 TableEntryAllocator> entry_map_;
-
-  // For detecting leak patterns in incoming allocations.
-  LeakAnalyzer leak_analyzer_;
-
-  DISALLOW_COPY_AND_ASSIGN(CallStackTable);
-};
-
-}  // namespace leak_detector
-}  // namespace metrics
-
-#endif  // COMPONENTS_METRICS_LEAK_DETECTOR_CALL_STACK_TABLE_H_