RemoteContentSuggestions: Stores the time of the last successful background fetch in a pref

components/ntp_snippets/remote/remote_suggestions_provider.cc

Index: components/ntp_snippets/remote/remote_suggestions_provider.cc
diff --git a/components/ntp_snippets/remote/remote_suggestions_provider.cc b/components/ntp_snippets/remote/remote_suggestions_provider.cc
index 653c82b401289a641bde225d90324a52c4239aa9..4ff354f6b697750382057030828db4b3d856afab 100644
--- a/components/ntp_snippets/remote/remote_suggestions_provider.cc
+++ b/components/ntp_snippets/remote/remote_suggestions_provider.cc
@@ -19,6 +19,7 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/task_runner_util.h"
+#include "base/time/default_tick_clock.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "components/data_use_measurement/core/data_use_user_data.h"
@@ -249,7 +250,8 @@ RemoteSuggestionsProvider::RemoteSuggestionsProvider(
       nuke_when_initialized_(false),
       thumbnail_requests_throttler_(
           pref_service,
-          RequestThrottler::RequestType::CONTENT_SUGGESTION_THUMBNAIL) {
+          RequestThrottler::RequestType::CONTENT_SUGGESTION_THUMBNAIL),
+      tick_clock_(base::MakeUnique<base::DefaultTickClock>()) {
   pref_service_->ClearPref(kDeprecatedSnippetHostsPref);
 
   RestoreCategoriesFromPrefs();
@@ -290,6 +292,7 @@ void RemoteSuggestionsProvider::RegisterProfilePrefs(
   registry->RegisterInt64Pref(prefs::kSnippetBackgroundFetchingIntervalWifi, 0);
   registry->RegisterInt64Pref(prefs::kSnippetBackgroundFetchingIntervalFallback,
                               0);
+  registry->RegisterInt64Pref(prefs::kLastSuccessfulBackgroundFetchTime, 0);
 
   RemoteSuggestionsStatusService::RegisterProfilePrefs(registry);
 }
@@ -331,7 +334,7 @@ void RemoteSuggestionsProvider::FetchSnippetsFromHosts(
   params.interactive_request = interactive_request;
   snippets_fetcher_->FetchSnippets(
       params, base::BindOnce(&RemoteSuggestionsProvider::OnFetchFinished,
-                             base::Unretained(this)));
+                             base::Unretained(this), interactive_request));
 }
 
 void RemoteSuggestionsProvider::Fetch(
@@ -641,6 +644,7 @@ void RemoteSuggestionsProvider::OnDatabaseError() {
 
 void RemoteSuggestionsProvider::OnFetchMoreFinished(
     const FetchDoneCallback& fetching_callback,
+    NTPSnippetsFetcher::FetchResult fetch_result,
     NTPSnippetsFetcher::OptionalFetchedCategories fetched_categories) {
   if (!fetched_categories) {
     // TODO(fhorschig): Disambiguate the kind of error that led here.
@@ -702,6 +706,8 @@ void RemoteSuggestionsProvider::OnFetchMoreFinished(
 }
 
 void RemoteSuggestionsProvider::OnFetchFinished(
+    bool interactive_request,
+    NTPSnippetsFetcher::FetchResult fetch_result,
     NTPSnippetsFetcher::OptionalFetchedCategories fetched_categories) {
   if (!ready()) {
     // TODO(tschumann): What happens if this was a user-triggered, interactive
@@ -709,6 +715,13 @@ void RemoteSuggestionsProvider::OnFetchFinished(
     return;
   }
 
+  // Record the fetch time of a successfull background fetch.
+  if (!interactive_request &&
+      fetch_result == NTPSnippetsFetcher::FetchResult::SUCCESS) {
+    pref_service_->SetInt64(prefs::kLastSuccessfulBackgroundFetchTime,

[tschumann, 2016/12/08 18:18:51]

just a comment -- no need to action: I guess that we might want to move this
later to a place where we actually consume this data (guess that's going to be
the remote-fetching-mastermind-class). You'll have to ask this class before we
do any fetches and it seems then just symmetrical to also tell that class about
the outcome of the fetch.

No need to do this right now (not sure about the state of this), but if this
sounds reasonable, a TODO() would be nice to find a proper home for this sort of
book-keeping.

+                            tick_clock_->NowTicks().ToInternalValue());
+  }
+
   // Mark all categories as not provided by the server in the latest fetch. The
   // ones we got will be marked again below.
   for (auto& item : category_contents_) {