[NTP Snippets] Reschedule background fetching on app upgrade if it was scheduled before

chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java
index 884e1eb135afaf30d97141bc122deb6302c92a62..ed6ca84ecc83b04f7a240240f17375735b55ea85 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeBackgroundService.java
@@ -120,6 +120,11 @@ public class ChromeBackgroundService extends GcmTaskService {
         SnippetsBridge.fetchSnippets(/*forceRequest=*/false);
     }
 
+    @VisibleForTesting
+    protected void rescheduleFetching() {
+        SnippetsBridge.rescheduleFetching();
+    }
+
     private void handlePrecache(Context context, String tag) {
         if (!hasPrecacheInstance()) {
             launchBrowser(context, tag);
@@ -202,9 +207,29 @@ public class ChromeBackgroundService extends GcmTaskService {
         }
     }
 
-    @Override
-    public void onInitializeTasks() {
+    @VisibleForTesting
+    protected void rescheduleBackgroundSyncTasksOnUpgrade() {
         BackgroundSyncLauncher.rescheduleTasksOnUpgrade(this);
+    }
+
+    @VisibleForTesting
+    protected void reschedulePrecacheTasksOnUpgrade() {
         PrecacheController.rescheduleTasksOnUpgrade(this);
     }
+
+    private void rescheduleSnippetsTasksOnUpgrade() {
+        if (SnippetsLauncher.shouldRescheduleTasksOnUpgrade()) {
+            if (!SnippetsLauncher.hasInstance()) {
+                launchBrowser(this, /*tag=*/""); // The |tag| doesn't matter here.
+            }
+            rescheduleFetching();
+        }
+    }
+
+    @Override
+    public void onInitializeTasks() {
+        rescheduleBackgroundSyncTasksOnUpgrade();
+        reschedulePrecacheTasksOnUpgrade();
+        rescheduleSnippetsTasksOnUpgrade();
+    }
 }