Refactor recording of the Startup.FirstWebContents.RenderProcessHostInit.ToNonEmptyPaint metric

components/startup_metric_utils/browser/startup_metric_utils.h

Index: components/startup_metric_utils/browser/startup_metric_utils.h
diff --git a/components/startup_metric_utils/browser/startup_metric_utils.h b/components/startup_metric_utils/browser/startup_metric_utils.h
index 6066d716056e51f2558e8b2acf85d513bdef8909..3a1e76f910982523a325ae903d0962fdbd652795 100644
--- a/components/startup_metric_utils/browser/startup_metric_utils.h
+++ b/components/startup_metric_utils/browser/startup_metric_utils.h
@@ -72,6 +72,10 @@ void RecordBrowserWindowDisplay(base::TimeTicks ticks);
 // Call this with the time delta that the browser spent opening its tabs.
 void RecordBrowserOpenTabsDelta(base::TimeDelta delta);
 
+// Call this with the time recorded when the first RenderProcessHost is
+// initialized, i.e. when we begin launching the first render process.
+void RecordFirstRenderProcessHostInit(base::TimeTicks ticks);
+
 // Call this with a renderer main entry time. The value provided for the first
 // call to this function is used to compute
 // Startup.LoadTime.BrowserMainToRendererMain. Further calls to this
@@ -84,9 +88,7 @@ void RecordFirstWebContentsMainFrameLoad(base::TimeTicks ticks);
 
 // Call this with the time when the first web contents had a non-empty paint,
 // only if the first web contents was unimpeded in its attempt to do so.
-void RecordFirstWebContentsNonEmptyPaint(
-    base::TimeTicks now,
-    base::TimeTicks render_process_host_init_time);
+void RecordFirstWebContentsNonEmptyPaint(base::TimeTicks ticks);
 
 // Call this with the time when the first web contents began navigating its main
 // frame. Adds a suffix to its metrics according to |workload|.