Snippets are enabled when search suggestions are enabled.

chrome/browser/profiles/profile_manager.cc

Index: chrome/browser/profiles/profile_manager.cc
diff --git a/chrome/browser/profiles/profile_manager.cc b/chrome/browser/profiles/profile_manager.cc
index 93a514c661c5c7ff8c884352d77100a423ca809f..6ecf084b9ebc2bbda87c7c2a8e43990c84f16329 100644
--- a/chrome/browser/profiles/profile_manager.cc
+++ b/chrome/browser/profiles/profile_manager.cc
@@ -108,7 +108,6 @@
 #endif
 
 #if defined(OS_ANDROID)
-#include "chrome/browser/android/chrome_feature_list.h"
 #include "chrome/browser/ntp_snippets/ntp_snippets_service_factory.h"
 #include "components/ntp_snippets/ntp_snippets_service.h"
 #endif
@@ -1232,8 +1231,7 @@ void ProfileManager::DoFinalInitForServices(Profile* profile,
   // Service is responsible for fetching content snippets for the NTP.
   // Note: Create the service even if the feature is disabled, so that any

[Michael van Ouwerkerk, 2016/05/20 12:38:36]

Marc, I don't understand this comment. Could you maybe suggest a rephrasing that
explains why we're instantiating the service even if it might be disabled?

[Marc Treib, 2016/05/20 13:49:36]

When the service is instantiated and enabled, it schedules a persistent and
recurring task for background fetching, at the Android OS level.
If the service gets disabled later, and we wouldn't instantiate it anymore, then
that task would remain active and would continue to wake up the device.

Does that clear things up?

   // remaining tasks will be cleaned up.
-  NTPSnippetsServiceFactory::GetForProfile(profile)->Init(
-      base::FeatureList::IsEnabled(chrome::android::kNTPSnippetsFeature));
+  NTPSnippetsServiceFactory::GetForProfile(profile)->Init();

[noyau (Ping after 24h), 2016/05/20 15:16:53]

Here the service is created and Init is called right away. Why do we need Init
in the first place? Can't the service "init" itself?

This Init pattern is not something I see used in KeyedServices, and it seems
more error prone than needed.

[noyau (Ping after 24h), 2016/05/24 14:19:11]

Ping!

[Michael van Ouwerkerk, 2016/05/24 14:38:54]

I don't know exactly why. It's possible some of the work done in Init requires a
fully constructed instance, but it's not documented... so now it's gone.

[Michael van Ouwerkerk, 2016/05/24 14:38:54]

Done.

[Bernhard Bauer, 2016/05/24 14:54:28]

The reason why this is here is because we need to start scheduling fetches as
soon as the browser starts. We could achieve this though by overriding
ServiceWillBeCreatedWithProfile in the factory and doing everything from Init()
in the constructor.

[Michael van Ouwerkerk, 2016/05/24 15:00:45]

I just moved everything to the constructor, I expect that's fine?

 #endif
 }