Implement UMA log throttling for cellular connections

components/metrics/profiler/profiler_metrics_provider.h

Index: components/metrics/profiler/profiler_metrics_provider.h
diff --git a/components/metrics/profiler/profiler_metrics_provider.h b/components/metrics/profiler/profiler_metrics_provider.h
index 8585fce554914fd1e945106da13fc758d0558233..af3e6a3efdaa37e067d8616ad2ad439b8e9278e2 100644
--- a/components/metrics/profiler/profiler_metrics_provider.h
+++ b/components/metrics/profiler/profiler_metrics_provider.h
@@ -22,7 +22,7 @@ namespace metrics {
 class ProfilerMetricsProvider : public MetricsProvider {
  public:
   explicit ProfilerMetricsProvider(
-      const base::Callback<bool(void)>& cellular_callback);
+      const base::Callback<void(bool*)>& cellular_callback);
   // Creates profiler metrics provider with a null callback.
   ProfilerMetricsProvider();
   ~ProfilerMetricsProvider() override;
@@ -53,9 +53,9 @@ class ProfilerMetricsProvider : public MetricsProvider {
   // profiling phase.
   std::map<int, ProfilerEventProto> profiler_events_cache_;
 
-  // Returns true if current connection type is cellular and user is assigned to
-  // experimental group for enabled cellular uploads.
-  base::Callback<bool(void)> cellular_callback_;
+  // Assigns true to output param if current connection type is cellular and
+  // user is assigned to experimental group for enabled cellular uploads.
+  base::Callback<void(bool*)> cellular_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfilerMetricsProvider);
 };