Reduce plugin_metrics_provider_ usage in MetricsService

chrome/browser/browser_process.h

Index: chrome/browser/browser_process.h
diff --git a/chrome/browser/browser_process.h b/chrome/browser/browser_process.h
index 8e46d93b16c2b7c35bc7d782e60cff54be826441..a76ee8ca28ee57e2e519e60fea3c05c3a53c797f 100644
--- a/chrome/browser/browser_process.h
+++ b/chrome/browser/browser_process.h
@@ -31,6 +31,7 @@ class MediaFileSystemRegistry;
 class MetricsService;
 class NetworkTimeTracker;
 class NotificationUIManager;
+class PluginMetricsProvider;
 class PrefRegistrySimple;
 class PrefService;
 class Profile;
@@ -104,6 +105,7 @@ class BrowserProcess {
 
   // Services: any of these getters may return NULL
   virtual MetricsService* metrics_service() = 0;
+  virtual PluginMetricsProvider* plugin_metrics_provider() = 0;

[Alexei Svitkine (slow), 2014/05/29 20:47:44]

I'd really like to hear Ilya's thoughts on this, but I'm not a big fan of
exposing the provider on g_browser_process.

I'd rather we expose MetricsServicesManager and for that have a method
"OnPluginLoadingError()" that the plugins code can call.

The reason I'd prefer the above is that I think we'll need to expose
MetricsServicesManager eventually anyway and it's cleaner to just have that
exposed than a bunch of smaller sub-parts (i.e. individual providers).

Then, PluginMetricsProvider would just be an implementation detail of the
metrics system and things wouldn't need to know about it.

Ilya, WDYT?

[Alexei Svitkine (slow), 2014/05/29 20:49:03]

(Just to clarify, my suggestion is to expose MetricsServicesManager and have a
method on that be plumbed through to the client and service.)

[Ilya Sherman, 2014/05/29 21:04:13]

Honestly, either approach is fine with me.  On the one hand, exposing just the
PluginMetricsProvider exposes a smaller API surface.  On the other hand, if
we're going to need to expose the MetricsServicesManager later on down the line
anyway, then there's not much harm to exposing it sooner rather than later.

[blundell, 2014/05/30 14:42:10]

Done.

   virtual rappor::RapporService* rappor_service() = 0;
   virtual ProfileManager* profile_manager() = 0;
   virtual PrefService* local_state() = 0;