Network traffic annotation added to image_data_fetcher.

chrome/browser/search/thumbnail_source.cc

Index: chrome/browser/search/thumbnail_source.cc
diff --git a/chrome/browser/search/thumbnail_source.cc b/chrome/browser/search/thumbnail_source.cc
index 2331ee0b1adbc68c205a50ceb56026989c16ac7a..277edff2587bd706eeb4f6c7a3d652e4230c4bf8 100644
--- a/chrome/browser/search/thumbnail_source.cc
+++ b/chrome/browser/search/thumbnail_source.cc
@@ -11,6 +11,7 @@
 #include "chrome/browser/thumbnails/thumbnail_service.h"
 #include "chrome/browser/thumbnails/thumbnail_service_factory.h"
 #include "chrome/common/url_constants.h"
+#include "net/traffic_annotation/network_traffic_annotation.h"
 #include "net/url_request/url_request.h"
 #include "url/gurl.h"
 
@@ -47,12 +48,45 @@ void ThumbnailSource::StartDataRequest(
     // If a local thumbnail is available for the page's URL, provide it.
     callback.Run(data.get());
   } else if (fallback_thumbnail_url.is_valid()) {
+    net::NetworkTrafficAnnotationTag traffic_annotation =
+        net::DefineNetworkTrafficAnnotation("thumbnail_source", R"(
+      semantics {
+        sender: "Thumbnail Source"
+        description:
+          "Retrieves thumbnails for site suggestions based on the user's "
+          "synced browsing history, for use e.g. on the New Tab page."
+        trigger:
+          "Triggered when a thumbnail for a suggestion is required (e.g. on "
+          "the New Tab page), and no local thumbnail is available."
+        data: "The URL for which to retrieve a thumbnail."
+        destination: GOOGLE_OWNED_SERVICE
+      }
+      policy {
+        cookies_allowed: false
+        setting:
+          "Users can disable this feature by signing out of Chrome, or "
+          "disabling Sync or History Sync in Chrome settings under 'Advanced "
+          "sync settings...'. The feature is enabled by default."
+        chrome_policy {
+          SyncDisabled {
+            policy_options {mode: MANDATORY}
+            SyncDisabled: true
+          }
+        }
+        chrome_policy {
+          SigninAllowed {
+            policy_options {mode: MANDATORY}
+            SigninAllowed: false
+          }
+        }
+      })");
     // Otherwise, if a fallback thumbnail URL was provided, fetch it and
     // eventually return it.
     image_data_fetcher_.FetchImageData(
         fallback_thumbnail_url,
         base::Bind(&ThumbnailSource::SendFetchedUrlImage,
-                   weak_ptr_factory_.GetWeakPtr(), callback));
+                   weak_ptr_factory_.GetWeakPtr(), callback),
+        traffic_annotation);
   } else {
     callback.Run(nullptr);
   }