Log messages regarding why app banners aren't displayed to the console

chrome/browser/banners/app_banner_manager.cc

Index: chrome/browser/banners/app_banner_manager.cc
diff --git a/chrome/browser/banners/app_banner_manager.cc b/chrome/browser/banners/app_banner_manager.cc
index fd3e65bc8e379ea08ff0f52ce8a964f75c9c7a30..fdbf80b17677caf4fe6eeca51a5d479730fdffaf 100644
--- a/chrome/browser/banners/app_banner_manager.cc
+++ b/chrome/browser/banners/app_banner_manager.cc
@@ -6,6 +6,7 @@
 
 #include "base/metrics/field_trial.h"
 #include "chrome/browser/banners/app_banner_data_fetcher.h"
+#include "chrome/browser/banners/app_banner_debug_log.h"
 #include "chrome/browser/banners/app_banner_settings_helper.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/render_frame_host.h"
@@ -50,8 +51,11 @@ void AppBannerManager::DidFinishLoad(
 
   // A secure origin is required to show banners, so exit early if we see the
   // URL is invalid.
-  if (!content::IsOriginSecure(validated_url) && !gDisableSecureCheckForTesting)
+  if (!content::IsOriginSecure(validated_url) &&
+      !gDisableSecureCheckForTesting) {
+    OutputDeveloperNotShownMessage(web_contents(), kNotServedFromSecureOrigin);
     return;
+  }
 
   // Kick off the data retrieval pipeline.
   data_fetcher_ = CreateAppBannerDataFetcher(weak_factory_.GetWeakPtr(),