[Offline Pages] Define separate watchdog timeout for concurrent bg loads

components/offline_pages/background/request_coordinator.h

Index: components/offline_pages/background/request_coordinator.h
diff --git a/components/offline_pages/background/request_coordinator.h b/components/offline_pages/background/request_coordinator.h
index e4970a0ba3a61d646197bda9d866947394d3c02f..8e0f265c6cde5950f1f72b83577822c7298abe1d 100644
--- a/components/offline_pages/background/request_coordinator.h
+++ b/components/offline_pages/background/request_coordinator.h
@@ -111,7 +111,8 @@ class RequestCoordinator : public KeyedService,
   // Starts processing of one or more queued save page later requests.
   // Returns whether processing was started and that caller should expect
   // a callback. If processing was already active, returns false.
-  bool StartProcessing(const DeviceConditions& device_conditions,
+  bool StartProcessing(bool is_background_scheduled,
+                       const DeviceConditions& device_conditions,
                        const base::Callback<void(bool)>& callback);
 
   // Stops the current request processing if active. This is a way for