Delete unused code from systeminfo.

webrtc/system_wrappers/source/cpu_info.cc

 /*
  *  Copyright (c) 2011 The WebRTC 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 in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/system_wrappers/include/cpu_info.h"
 
-#include "webrtc/base/systeminfo.h"
+#if defined(WEBRTC_WIN)
+#include <winsock2.h>
+#include <windows.h>
+#ifndef EXCLUDE_D3D9
+#include <d3d9.h>
+#endif
+#elif defined(WEBRTC_LINUX)
+#include <unistd.h>
+#endif
+#if defined(WEBRTC_MAC)
+#include <sys/sysctl.h>
+#endif
+
+#include "webrtc/base/logging.h"
+
+namespace internal {
+static int DetectNumberOfCores() {
+  // We fall back on assuming a single core in case of errors.
+  int number_of_cores = 1;
+
+#if defined(WEBRTC_WIN)
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  number_of_cores = static_cast<int>(si.dwNumberOfProcessors);
+#elif defined(WEBRTC_LINUX) || defined(WEBRTC_ANDROID)
+  number_of_cores = static_cast<int>(sysconf(_SC_NPROCESSORS_ONLN));
+#elif defined(WEBRTC_MAC)
+  int name[] = {CTL_HW, HW_AVAILCPU};
+  size_t size = sizeof(number_of_cores);
+  if (0 != sysctl(name, 2, &number_of_cores, &size, NULL, 0)) {
+    LOG(LS_ERROR) << "Failed to get number of cores";
+    number_of_cores = 1;
+  }
+#else
+  LOG(LS_ERROR) << "No function to get number of cores";
+#endif
+
+  LOG(LS_INFO) << "Available number of cores: " << number_of_cores;
+
+  return number_of_cores;
+}
+}
 
 namespace webrtc {
 
 uint32_t CpuInfo::DetectNumberOfCores() {
-  return static_cast<uint32_t>(rtc::SystemInfo::GetMaxCpus());
+  // Statically cache the number of system cores available since if the process
+  // is running in a sandbox, we may only be able to read the value once (before
+  // the sandbox is initialized) and not thereafter.
+  // For more information see crbug.com/176522.
+  static uint32_t logical_cpus = 0;
+  if (!logical_cpus)
+    logical_cpus = static_cast<uint32_t>(internal::DetectNumberOfCores());
+  return logical_cpus;
 }
 
 }  // namespace webrtc