Use TimeTicks instead of gettimeofday in ProcessMetrics.

base/process/process_metrics.h

Index: base/process/process_metrics.h
diff --git a/base/process/process_metrics.h b/base/process/process_metrics.h
index 45f2ef9d594407d4b7de0e00c781e0b518a529e0..ec16d4f9c2ee9ecbe150e7638120f08984bb57c2 100644
--- a/base/process/process_metrics.h
+++ b/base/process/process_metrics.h
@@ -205,11 +205,11 @@ class BASE_EXPORT ProcessMetrics {
 
   // Used to store the previous times and CPU usage counts so we can
   // compute the CPU usage between calls.
-  int64 last_cpu_time_;
+  TimeTicks last_cpu_walltime_;

[Mark Mentovai, 2014/01/23 19:38:01]

This (and line 212) aren’t “wall time” if they’re TimeTicks, they’re “ticks.”

[Nico, 2014/01/23 19:40:50]

Right, but the linux version already has a last_cpu in "jiffies", and it's
roughly walltime. It's a better name than "cpu time", which this isn't :-)

ticks are ~microseconds in real time, so I think the name isn't so bad?

   int64 last_system_time_;
 
   // Same thing for idle wakeups.
-  int64 last_idle_wakeups_time_;
+  TimeTicks last_idle_wakeups_walltime_;
   int64 last_absolute_idle_wakeups_;
 
 #if !defined(OS_IOS)
@@ -219,7 +219,7 @@ class BASE_EXPORT ProcessMetrics {
 
   PortProvider* port_provider_;
 #elif defined(OS_POSIX)
-  // Jiffie count at the last_cpu_time_ we updated.
+  // Jiffie count at the last_cpu_walltime_ we updated.
   int last_cpu_;
 #endif  // defined(OS_POSIX)
 #endif  // !defined(OS_IOS)