Create the BackgroundFetchBatchManager and initiate a download.

content/browser/BUILD.gn

Index: content/browser/BUILD.gn
diff --git a/content/browser/BUILD.gn b/content/browser/BUILD.gn
index c8d27f5c2a01a8f7bb0171fabc6cd4f42d2ad90e..01983570780e0e4939f863f1755755eb4ca4f62a 100644
--- a/content/browser/BUILD.gn
+++ b/content/browser/BUILD.gn
@@ -316,10 +316,14 @@ source_set("browser") {
     "appcache/chrome_appcache_service.h",
     "audio_manager_thread.cc",
     "audio_manager_thread.h",
+    "background_fetch/background_fetch_batch_manager.cc",
+    "background_fetch/background_fetch_batch_manager.h",
     "background_fetch/background_fetch_context.cc",
     "background_fetch/background_fetch_context.h",
     "background_fetch/background_fetch_data_manager.cc",
     "background_fetch/background_fetch_data_manager.h",
+    "background_fetch/batch_request.cc",
+    "background_fetch/batch_request.h",

[Peter Beverloo, 2017/02/23 12:14:55]

These files aren't included in this CL?

[harkness, 2017/02/23 17:08:40]

Added them. Unfortunately, because they weren't added before, when I was working
on the follow-up, I was editing the original files. So now the follow-up is just
going to be a new patch set on this CL. Sorry about that.

     "background_fetch/fetch_request.cc",
     "background_fetch/fetch_request.h",
     "background_sync/background_sync_context.cc",