Revert of components/metrics: Add runtime memory leak detector

components/metrics/leak_detector/call_stack_manager.cc

-// 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.
-
-#include "components/metrics/leak_detector/call_stack_manager.h"
-
-#include <algorithm>  // For std::copy.
-#include <new>
-
-#include "base/hash.h"
-#include "components/metrics/leak_detector/custom_allocator.h"
-
-namespace metrics {
-namespace leak_detector {
-
-CallStackManager::CallStackManager() {}
-
-CallStackManager::~CallStackManager() {
-  for (CallStack* call_stack : call_stacks_) {
-    CustomAllocator::Free(call_stack->stack,
-                          call_stack->depth * sizeof(*call_stack->stack));
-    call_stack->stack = nullptr;
-    call_stack->depth = 0;
-
-    CustomAllocator::Free(call_stack, sizeof(CallStack));
-  }
-  call_stacks_.clear();
-}
-
-const CallStack* CallStackManager::GetCallStack(size_t depth,
-                                                const void* const stack[]) {
-  // Temporarily create a call stack object for lookup in |call_stacks_|.
-  CallStack temp;
-  temp.depth = depth;
-  temp.stack = const_cast<const void**>(stack);
-  // This is the only place where the call stack's hash is computed. This value
-  // can be reused in the created object to avoid further hash computation.
-  temp.hash =
-      base::Hash(reinterpret_cast<const char*>(stack), sizeof(*stack) * depth);
-
-  auto iter = call_stacks_.find(&temp);
-  if (iter != call_stacks_.end())
-    return *iter;
-
-  // Since |call_stacks_| stores CallStack pointers rather than actual objects,
-  // create new call objects manually here.
-  CallStack* call_stack =
-      new (CustomAllocator::Allocate(sizeof(CallStack))) CallStack;
-  call_stack->depth = depth;
-  call_stack->hash = temp.hash;  // Don't run the hash function again.
-  call_stack->stack = reinterpret_cast<const void**>(
-      CustomAllocator::Allocate(sizeof(*stack) * depth));
-  std::copy(stack, stack + depth, call_stack->stack);
-
-  call_stacks_.insert(call_stack);
-  return call_stack;
-}
-
-bool CallStackManager::CallStackPointerEqual::operator()(
-    const CallStack* c1,
-    const CallStack* c2) const {
-  return c1->depth == c2->depth && c1->hash == c2->hash &&
-         std::equal(c1->stack, c1->stack + c1->depth, c2->stack);
-}
-
-}  // namespace leak_detector
-}  // namespace metrics