Refactoring DownloadManager::DownloadURL to add proper annotation.

content/public/browser/download_manager.h

Index: content/public/browser/download_manager.h
diff --git a/content/public/browser/download_manager.h b/content/public/browser/download_manager.h
index f6080fe5df2fa375ec65a05787eac3c6a881163d..038195b894e1f7d762348b7f41c6090b72f15fb6 100644
--- a/content/public/browser/download_manager.h
+++ b/content/public/browser/download_manager.h
@@ -40,6 +40,7 @@
 #include "content/public/browser/download_item.h"
 #include "content/public/browser/download_url_parameters.h"
 #include "net/base/net_errors.h"
+#include "net/traffic_annotation/network_traffic_annotation.h"
 
 class GURL;
 
@@ -121,7 +122,8 @@ class CONTENT_EXPORT DownloadManager : public base::SupportsUserData::Data {
 
   // See DownloadUrlParameters for details about controlling the download.
   virtual void DownloadUrl(
-      std::unique_ptr<DownloadUrlParameters> parameters) = 0;
+      std::unique_ptr<DownloadUrlParameters> parameters,
+      const net::NetworkTrafficAnnotationTag& traffic_annotation) = 0;

[David Trainor- moved to gerrit, 2017/05/30 16:35:57]

Should the be part of DownloadUrlParameters?  We can default it to
NO_TRAFFIC_ANNOTATION_YET.  I don't feel too strongly either way, especially
since we're going to mandate this for every request, but it might make the
plumbing cleaner.

[Ramin Halavati, 2017/05/31 05:16:01]

We will gradually remove all NO_TRAFFIC_ANNOTATION_YET tags, they are temporary
until all call sites are properly annotated.
I am also not strongly towards current approach, but this is more similar to the
rest of repository and if we add a default UNASSIGNED value, we would need to
have online checks to find if it is properly annotated.

 
   // Allow objects to observe the download creation process.
   virtual void AddObserver(Observer* observer) = 0;