Reland of Fix computation of runtime for throttled tasks

components/scheduler/base/time_domain.h

Index: components/scheduler/base/time_domain.h
diff --git a/components/scheduler/base/time_domain.h b/components/scheduler/base/time_domain.h
index fe1788c98cacec62f7e1da2c577c547f0f53c00a..1b37fed830ae24d7d640002a40da28126ae8961f 100644
--- a/components/scheduler/base/time_domain.h
+++ b/components/scheduler/base/time_domain.h
@@ -48,6 +48,13 @@
 
   // Evaluate this TimeDomain's Now. Can be called from any thread.
   virtual base::TimeTicks Now() const = 0;
+
+  // Computes a runtime which is >= |time_domain_now| + |delay|. This is used to
+  // allow the TimeDomain to decide if the real or virtual time should be used
+  // when computing the task run time.  This can be called from any thread.
+  virtual base::TimeTicks ComputeDelayedRunTime(
+      base::TimeTicks time_domain_now,
+      base::TimeDelta delay) const = 0;
 
   // Some TimeDomains support virtual time, this method tells us to advance time
   // if possible and return true if time was advanced.