[NTP Snippets] Refactor background scheduling for remote suggestions

chrome/browser/android/ntp/ntp_snippets_launcher.h

Index: chrome/browser/android/ntp/ntp_snippets_launcher.h
diff --git a/chrome/browser/android/ntp/ntp_snippets_launcher.h b/chrome/browser/android/ntp/ntp_snippets_launcher.h
index 2dfbb4bafeca2bd7a48ebde53d3e63c432cc55fc..bd163a08720692d5599fbd660ad958b2cf54a39a 100644
--- a/chrome/browser/android/ntp/ntp_snippets_launcher.h
+++ b/chrome/browser/android/ntp/ntp_snippets_launcher.h
@@ -9,12 +9,13 @@
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/time/time.h"
-#include "components/ntp_snippets/remote/ntp_snippets_scheduler.h"
+#include "components/ntp_snippets/remote/persistent_scheduler.h"
 
 // Android implementation of ntp_snippets::NTPSnippetsScheduler.
 // The NTPSnippetsLauncher singleton owns the Java SnippetsLauncher object, and
 // is used to schedule the fetching of snippets. Runs on the UI thread.
-class NTPSnippetsLauncher : public ntp_snippets::NTPSnippetsScheduler {
+class NTPSnippetsLauncher
+    : public ntp_snippets::PersistentScheduler {

[tschumann, 2016/12/15 14:12:11]

sorry for joining the naming discussion so late.
Will there be further implementations of the PersistentScheduler interface?

Would the soft schedules also happen through an implementation of this?
I think what we really have here is a PeriodicTask. IMO, we are still mixing up
the concepts a bit about what are signals that influence the fetch-scheduling
and what is part of the actual scheduler.

(see further comments on PersistentScheduler::Listener).

I also see that we need to make progress here and volunteer to help with further
renamings. But that would be a topic I'd quickly like to discuss first, and then
see what's the quickest way to get us there.

[jkrcal, 2016/12/19 09:40:24]

No, this is meant just for the OS-dependent scheduler for persistent periodic
tasks. Based on an offline discussion, kept as it is.

  public:
   static NTPSnippetsLauncher* Get();