Change outputting ints in win/linux GetCpuUsage to doubles.

base/process/process_metrics_win.cc

 // Copyright (c) 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 "base/process/process_metrics.h"
 
 #include <windows.h>
 #include <psapi.h>
 
 #include "base/logging.h"
@@ skipping 207 matching lines @@
     return 0;
   }
 
   int64 system_time_delta = system_time - last_system_time_;
   // FILETIME is in 100-nanosecond units, so this needs microseconds times 10.
   int64 time_delta = (time - last_cpu_time_).InMicroseconds() * 10;
   DCHECK_NE(0U, time_delta);
   if (time_delta == 0)
     return 0;
 
-  // We add time_delta / 2 so the result is rounded.
-  int cpu = static_cast<int>((system_time_delta * 100 + time_delta / 2) /
-                             time_delta);
 
   last_system_time_ = system_time;
   last_cpu_time_ = time;
 
-  return cpu;
+  return static_cast<double>(system_time_delta * 100.0) / time_delta;
 }
 
 bool ProcessMetrics::GetIOCounters(IoCounters* io_counters) const {
   return GetProcessIoCounters(process_, io_counters) != FALSE;
 }
 
 ProcessMetrics::ProcessMetrics(ProcessHandle process)
     : process_(process),
       processor_count_(base::SysInfo::NumberOfProcessors()),
       last_system_time_(0) {
@@ skipping 36 matching lines @@
     return 0;
   }
   return (info.CommitTotal * system_info.dwPageSize) / 1024;
 }
 
 size_t GetPageSize() {
   return PAGESIZE_KB * 1024;
 }
 
 }  // namespace base