Add Startup Timing to CPM

base/time.h

 // Copyright (c) 2012 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.
 
 // Time represents an absolute point in time, internally represented as
 // microseconds (s/1,000,000) since a platform-dependent epoch.  Each
 // platform's epoch, along with other system-dependent clock interface
 // routines, is defined in time_PLATFORM.cc.
 //
 // TimeDelta represents a duration of time, internally represented in
@@ skipping 63 matching lines @@
   }
 
   // Returns the internal numeric value of the TimeDelta object. Please don't
   // use this and do arithmetic on it, as it is more error prone than using the
   // provided operators.
   // For serializing, use FromInternalValue to reconstitute.
   int64 ToInternalValue() const {
     return delta_;
   }
 
+  // Returns true if this object has not been initialized.
+  bool is_null() const {

[Yoyo Zhou, 2012/07/31 09:57:32]

I'm not sure this is right. A delta of 0 could actually be valid (whereas a Time
of 0 is not).

[Devlin, 2012/07/31 16:43:40]

Oooh, good point. I was wondering why there wasn't already one of these... :)
Done.

+    return delta_ == 0;
+  }
+
 #if defined(OS_POSIX)
   struct timespec ToTimeSpec() const;
 #endif
 
   // Returns the time delta in some unit. The F versions return a floating
   // point value, the "regular" versions return a rounded-down value.
   //
   // InMillisecondsRoundedUp() instead returns an integer that is rounded up
   // to the next full millisecond.
   int InDays() const;
@@ skipping 505 matching lines @@
 #endif
 };
 
 inline TimeTicks TimeDelta::operator+(TimeTicks t) const {
   return TimeTicks(t.ticks_ + delta_);
 }
 
 }  // namespace base
 
 #endif  // BASE_TIME_H_