Snippets are enabled when search suggestions are enabled.

chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc

Index: chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
diff --git a/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc b/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
index 140656102b52617c4e9e6367a808aeefcb41785b..092c5fad4a1f6a545ac292254c9c7f3c820de5ad 100644
--- a/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
+++ b/chrome/browser/ntp_snippets/ntp_snippets_service_factory.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/ntp_snippets/ntp_snippets_service_factory.h"
 
+#include "base/feature_list.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/singleton.h"
 #include "chrome/browser/browser_process.h"
@@ -13,11 +14,13 @@
 #include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/common/channel_info.h"
+#include "chrome/common/pref_names.h"
 #include "components/image_fetcher/image_fetcher.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/ntp_snippets/ntp_snippets_fetcher.h"
 #include "components/ntp_snippets/ntp_snippets_scheduler.h"
 #include "components/ntp_snippets/ntp_snippets_service.h"
+#include "components/prefs/pref_service.h"
 #include "components/safe_json/safe_json_parser.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_manager.h"
@@ -28,6 +31,7 @@
 #include "net/url_request/url_request_context_getter.h"
 
 #if defined(OS_ANDROID)
+#include "chrome/browser/android/chrome_feature_list.h"
 #include "chrome/browser/android/ntp/ntp_snippets_launcher.h"
 #endif  // OS_ANDROID
 
@@ -63,6 +67,13 @@ NTPSnippetsServiceFactory::~NTPSnippetsServiceFactory() {}
 KeyedService* NTPSnippetsServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
   Profile* profile = Profile::FromBrowserContext(context);
+
+  bool enabled = profile->GetPrefs()->GetBoolean(prefs::kSearchSuggestEnabled);
+#if defined(OS_ANDROID)
+  enabled = enabled &&
+            base::FeatureList::IsEnabled(chrome::android::kNTPSnippetsFeature);

[Bernhard Bauer, 2016/05/20 10:43:24]

Hm... both of these things use APIs that are available in components/, just the
keys (prefs::kSearchSuggestEnabled / chrome::android::kNTPSnippetsFeature) are
from chrome/. We could think about moving this into the component as well and
just passing the keys in. That might be particularly interesting once we start
observing pref changes, as then the NTPSnippetsService could observe the pref
directly and we wouldn't have to have an additional object for that.

[Michael van Ouwerkerk, 2016/05/20 11:25:58]

Agreed. I've added a TODO along those lines.

+#endif  // OS_ANDROID
+
   SigninManagerBase* signin_manager =
       SigninManagerFactory::GetForProfile(profile);
   OAuth2TokenService* token_service =
@@ -85,7 +96,7 @@ KeyedService* NTPSnippetsServiceFactory::BuildServiceInstanceFor(
               base::SequencedWorkerPool::CONTINUE_ON_SHUTDOWN);
 
   return new ntp_snippets::NTPSnippetsService(
-      profile->GetPrefs(), suggestions_service, task_runner,
+      enabled, profile->GetPrefs(), suggestions_service, task_runner,
       g_browser_process->GetApplicationLocale(), scheduler,
       base::WrapUnique(new ntp_snippets::NTPSnippetsFetcher(
           signin_manager, token_service, request_context,