Teach Background Fetch how to start a new fetch.

content/browser/background_fetch/background_fetch_job_controller.h

Index: content/browser/background_fetch/background_fetch_job_controller.h
diff --git a/content/browser/background_fetch/background_fetch_job_controller.h b/content/browser/background_fetch/background_fetch_job_controller.h
index 90ef6fb3b6a6b11e763403ec96d597026d375ba7..6d97a3437f157e7e931ce2d045b7975985e666a1 100644
--- a/content/browser/background_fetch/background_fetch_job_controller.h
+++ b/content/browser/background_fetch/background_fetch_job_controller.h
@@ -12,6 +12,7 @@
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
+#include "content/browser/background_fetch/background_fetch_registration_id.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/download_item.h"
 
@@ -28,11 +29,12 @@ class StoragePartition;
 class CONTENT_EXPORT BackgroundFetchJobController
     : public DownloadItem::Observer {
  public:
-  BackgroundFetchJobController(const std::string& job_guid,
-                               BrowserContext* browser_context,
-                               StoragePartition* storage_partition,
-                               std::unique_ptr<BackgroundFetchJobData> job_data,
-                               base::OnceClosure completed_closure);
+  BackgroundFetchJobController(
+      const BackgroundFetchRegistrationId& registration_id,
+      BrowserContext* browser_context,
+      StoragePartition* storage_partition,
+      std::unique_ptr<BackgroundFetchJobData> job_data,
+      base::OnceClosure completed_closure);
   ~BackgroundFetchJobController() override;
 
   // Start processing on a batch of requests. Some of these may already be in
@@ -42,6 +44,10 @@ class CONTENT_EXPORT BackgroundFetchJobController
   // Called by the BackgroundFetchContext when the system is shutting down.
   void Shutdown();
 
+  const BackgroundFetchRegistrationId& registration_id() const {
+    return registration_id_;
+  }
+
  private:
   // DownloadItem::Observer methods.
   void OnDownloadUpdated(DownloadItem* item) override;
@@ -55,6 +61,8 @@ class CONTENT_EXPORT BackgroundFetchJobController
 
   void ProcessRequest(const BackgroundFetchRequestInfo& request);
 
+  BackgroundFetchRegistrationId registration_id_;
+
   // Pointer to the browser context. The BackgroundFetchJobController is owned
   // by the BrowserContext via the StoragePartition.
   // TODO(harkness): Currently this is only used to lookup the DownloadManager.