Network traffic annotation added to update_client.

components/update_client/url_fetcher_downloader.cc

Index: components/update_client/url_fetcher_downloader.cc
diff --git a/components/update_client/url_fetcher_downloader.cc b/components/update_client/url_fetcher_downloader.cc
index 4dcd36e65e4c3e0c3e6801fb56e6e18440246cc9..bd5cfe6fe1ba17aa49467bead729a9f2499b98ee 100644
--- a/components/update_client/url_fetcher_downloader.cc
+++ b/components/update_client/url_fetcher_downloader.cc
@@ -15,6 +15,7 @@
 #include "components/data_use_measurement/core/data_use_user_data.h"
 #include "components/update_client/utils.h"
 #include "net/base/load_flags.h"
+#include "net/traffic_annotation/network_traffic_annotation.h"
 #include "net/url_request/url_fetcher.h"
 #include "url/gurl.h"
 
@@ -36,7 +37,31 @@ UrlFetcherDownloader::~UrlFetcherDownloader() {
 void UrlFetcherDownloader::DoStartDownload(const GURL& url) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  url_fetcher_ = net::URLFetcher::Create(0, url, net::URLFetcher::GET, this);
+  net::NetworkTrafficAnnotationTag traffic_annotation =
+      net::DefineNetworkTrafficAnnotation("url_fetcher_downloader", R"(
+        semantics {
+          sender: "Component Updater"
+          description:
+            "The component updater in Chrome is responsible for updating code "
+            "and data modules such as Flash, CrlSet, Origin Trials, etc. These "
+            "modules are updated on cycles independent of the Chrome release "
+            "tracks. It runs in the browser process and communicates with a "
+            "set of servers using the Omaha protocol to find the latest "
+            "versions of components, download them, and register them with the "
+            "rest of Chrome."
+          trigger: "Manual or automatic software updates."
+          data:
+            "The URL that refers to a CRX. It is usually obfuscated, but this "

[msramek, 2017/05/18 09:45:46]

Should we just say "component" instead of "CRX"? I assume that the abbreviation
is kinda well known, but still... this is for an external reader.

[Ramin Halavati, 2017/05/18 10:44:01]

Done.

[Ramin Halavati, 2017/05/18 10:44:01]

Done.

+            "may be overriden."

[msramek, 2017/05/18 09:45:46]

I would try to clarify a bit when things are obfuscated and when not. If I
understand Sorin's comment correctly, a component is usually published on an
obfuscated URL, but for some components we decided to publish them on a
non-obfuscated?

Then I would say something like "The URL is obfuscated for most components".

+          destination: GOOGLE_OWNED_SERVICE
+        }
+        policy {
+          cookies_allowed: false
+          setting: "This feature cannot be disabled."
+          policy_exception_justification: "Not implemented."

[msramek, 2017/05/18 09:45:46]

What about the
https://www.chromium.org/administrators/policy-list-3#ComponentUpdatesEnabled
policy?

[Ramin Halavati, 2017/05/18 10:44:01]

Done.

+        })");
+  url_fetcher_ = net::URLFetcher::Create(0, url, net::URLFetcher::GET, this,
+                                         traffic_annotation);
   url_fetcher_->SetRequestContext(context_getter_);
   url_fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
                              net::LOAD_DO_NOT_SAVE_COOKIES |