extensions: Add CPU temperatures field to system.cpu.getInfo() function

extensions/browser/api/system_cpu/cpu_info_provider.cc

 // Copyright 2013 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 "extensions/browser/api/system_cpu/cpu_info_provider.h"
 
 #include "base/sys_info.h"
 
+#if defined(OS_CHROMEOS)
+#include "chromeos/system/cpu_temperature_reader.h"
+#endif  // defined(OS_CHROMEOS)
+
 namespace extensions {
 
 using api::system_cpu::CpuInfo;
 
 // Static member intialization.
 base::LazyInstance<scoped_refptr<CpuInfoProvider>>::DestructorAtExit
     CpuInfoProvider::provider_ = LAZY_INSTANCE_INITIALIZER;
 
 CpuInfoProvider::CpuInfoProvider() {
 }
@@ skipping 13 matching lines @@
   info_.model_name = base::SysInfo::CPUModelName();
   info_.features = GetFeatures();
 
   info_.processors.clear();
   // Fill in the correct number of uninitialized ProcessorInfos.
   for (int i = 0; i < info_.num_of_processors; ++i)
     info_.processors.push_back(api::system_cpu::ProcessorInfo());
   // Initialize the ProcessorInfos, or return an empty array if that fails.
   if (!QueryCpuTimePerProcessor(&info_.processors))
     info_.processors.clear();
+
+#if defined(OS_CHROMEOS)
+  info_.temperatures.clear();

[Devlin, 2017/04/26 02:04:59]

what is this clear()ing?

[Simon Que, 2017/04/26 02:27:21]

CpuInfoProvider is a singleton class. |info_| retains its state between calls to
QueryInfo(), so the vectors must be cleared. See above, for example:
"info_.processors.clear();"

+  auto cpu_temp_info =
+      chromeos::system::CPUTemperatureReader().GetCPUTemperatures();

[Devlin, 2017/04/26 02:04:58]

GetCPUTemperatures() doesn't make it clear what the return result is.  Refrain
from using auto.

[Simon Que, 2017/04/26 02:27:21]

Done.

+  for (const auto& info : cpu_temp_info) {

[Devlin, 2017/04/26 02:04:59]

info_.temperatures.reserve(cpu_temp_info.size())

[Simon Que, 2017/04/26 02:27:21]

Done.

+    info_.temperatures.push_back(info.temp_celsius);
+  }
+#endif  // defined(OS_CHROMEOS)
+
   return true;
 }
 
 std::vector<std::string> CpuInfoProvider::GetFeatures() const {
   std::vector<std::string> features;
   // These are the feature codes used by /proc/cpuinfo on Linux.
   if (cpu_.has_mmx())
     features.push_back("mmx");
   if (cpu_.has_sse())
     features.push_back("sse");
@@ skipping 13 matching lines @@
 }
 
 // static
 CpuInfoProvider* CpuInfoProvider::Get() {
   if (provider_.Get().get() == NULL)
     provider_.Get() = new CpuInfoProvider();
   return provider_.Get().get();
 }
 
 }  // namespace extensions