Use a monotonic clock (TimeTicks) to report network times to WebCore.

base/time.h

Index: base/time.h
diff --git a/base/time.h b/base/time.h
index aa97f0ab4f422c807247e5c226b565fff21ac6c8..8582ba8529fa24185e9091c1cd7a000a2c1135c9 100644
--- a/base/time.h
+++ b/base/time.h
@@ -464,7 +464,8 @@ class BASE_EXPORT TimeTicks {
 
   // Platform-dependent tick count representing "right now."
   // The resolution of this clock is ~1-15ms.  Resolution varies depending
-  // on hardware/operating system configuration.
+  // on hardware/operating system configuration.  The value should be the same
+  // across processes.

[wtc, 2011/08/29 21:59:41]

Nit: this comment is a little unclear.  You can perhaps say
that time origin (time 0) should be the same across processes,
and give the system boot time as an example of time 0.

The reason I asked to have darin or brettw look at this is
to ensure that this is a requirement that we can commit to.

   static TimeTicks Now();
 
   // Returns a platform-dependent high-resolution tick count. Implementation
@@ -492,6 +493,14 @@ class BASE_EXPORT TimeTicks {
     return ticks_;
   }
 
+  // Converts an integer value representing TimeTicks to a class. This is used
+  // when deserializing a |TimeTicks| structure, using a value that originated
+  // from |TimeTicks::ToInternalValue()|. It is not provided as a constructor
+  // because the integer type may be unclear from the perspective of a caller.
+  static TimeTicks FromInternalValue(int64 ticks) {
+    return TimeTicks(ticks);
+  }
+
   TimeTicks& operator=(TimeTicks other) {
     ticks_ = other.ticks_;
     return *this;