Added DownloadItem::Observer to JobController.

content/browser/background_fetch/background_fetch_context.h

Index: content/browser/background_fetch/background_fetch_context.h
diff --git a/content/browser/background_fetch/background_fetch_context.h b/content/browser/background_fetch/background_fetch_context.h
index 49f377fb33102c1a6d564596206dc9e028e7be65..733e2843585f49504e6bff4c5a52e2edbdd2708c 100644
--- a/content/browser/background_fetch/background_fetch_context.h
+++ b/content/browser/background_fetch/background_fetch_context.h
@@ -41,6 +41,11 @@ class CONTENT_EXPORT BackgroundFetchContext
   // Shutdown must be called before deleting this. Call on the UI thread.
   void Shutdown();
 
+  // Called by the JobController to inform the context that the job is complete.
+  // TODO(harkness): Pass back enough information that the context can construct
+  // the Mojo response.
+  void JobComplete(const std::string& job_guid);

[Peter Beverloo, 2017/03/08 14:58:19]

Could we instead give the JobController a base::callback that it calls when a
job is complete? That would allow you to make this private, and would help
testing down the road too.

[harkness, 2017/03/10 13:33:53]

I agree with using callbacks, but this hadn't been hooked up at all, so I've
just removed it for now. When I add it back it will be with callbacky goodness.

+
   BackgroundFetchDataManager* GetDataManagerForTesting() {
     return &background_fetch_data_manager_;
   }