Allow dumping raw json fetched from the server.

components/ntp_snippets/ntp_snippets_service.cc

Index: components/ntp_snippets/ntp_snippets_service.cc
diff --git a/components/ntp_snippets/ntp_snippets_service.cc b/components/ntp_snippets/ntp_snippets_service.cc
index af047ac3af7da517dda41c378aa711cfd3cecd9c..ea575674ca800812191fb4cdb0284cbb242fba71 100644
--- a/components/ntp_snippets/ntp_snippets_service.cc
+++ b/components/ntp_snippets/ntp_snippets_service.cc
@@ -347,6 +347,8 @@ void NTPSnippetsService::OnSnippetsDownloaded(
   if (!snippets_json.empty()) {
     DCHECK(status.empty());
 
+    last_fetch_json_ = snippets_json;
+
     parse_json_callback_.Run(
         snippets_json,
         base::Bind(&NTPSnippetsService::OnJsonParsed,
@@ -422,11 +424,6 @@ bool NTPSnippetsService::LoadFromListValue(const base::ListValue& list) {
                    std::make_move_iterator(new_snippets.begin()),
                    std::make_move_iterator(new_snippets.end()));
 
-  // If there are more snippets now than we want to show, drop the extra ones
-  // from the end of the list.
-  if (snippets_.size() > kMaxSnippetCount)
-    snippets_.resize(kMaxSnippetCount);
-
   return true;
 }
 
@@ -484,6 +481,12 @@ void NTPSnippetsService::LoadingSnippetsFinished() {
                        return snippet->expiry_date() <= expiry;
                      }),
       snippets_.end());
+
+  // If there are more snippets now than we want to show, drop the extra ones
+  // from the end of the list.
+  if (snippets_.size() > kMaxSnippetCount)
+    snippets_.resize(kMaxSnippetCount);
+
   StoreSnippetsToPrefs();
 
   discarded_snippets_.erase(