Make stack sampling profiler sample beyond startup.

components/metrics/child_call_stack_profile_collector.h

Index: components/metrics/child_call_stack_profile_collector.h
diff --git a/components/metrics/child_call_stack_profile_collector.h b/components/metrics/child_call_stack_profile_collector.h
index 7eb3abae8146517dc7863d49f8c77b9d3fee59ff..d4883604bd5dde7fafc36bf86cbe83feeb9cb204 100644
--- a/components/metrics/child_call_stack_profile_collector.h
+++ b/components/metrics/child_call_stack_profile_collector.h
@@ -90,9 +90,14 @@ class ChildCallStackProfileCollector {
 
   using CallStackProfile = base::StackSamplingProfiler::CallStackProfile;
 
-  void Collect(const CallStackProfileParams& params,
+  bool Collect(const CallStackProfileParams& params,
                base::TimeTicks start_timestamp,
-               std::vector<CallStackProfile> profiles);
+               std::vector<CallStackProfile> profiles,
+               base::StackSamplingProfiler::SamplingParams* sampling_params);
+
+  void CollectImpl(const CallStackProfileParams& params,
+                   base::TimeTicks start_timestamp,
+                   std::vector<CallStackProfile> profiles);
 
   // This object may be accessed on any thread, including the profiler
   // thread. The expected use case for the object is to be created and have