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content/test/content_browser_test_utils_internal.cc

Index: content/test/content_browser_test_utils_internal.cc
diff --git a/content/test/content_browser_test_utils_internal.cc b/content/test/content_browser_test_utils_internal.cc
index 5b889c3f3eaded6729611b2b4136dc3dc4b54bb4..207227e263637a7491ea2494763dd6c03196babc 100644
--- a/content/test/content_browser_test_utils_internal.cc
+++ b/content/test/content_browser_test_utils_internal.cc
@@ -210,9 +210,11 @@ std::string FrameTreeVisualizer::DepictFrameTree(FrameTreeNode* root) {
   for (auto& legend_entry : legend) {
     SiteInstanceImpl* site_instance =
         static_cast<SiteInstanceImpl*>(legend_entry.second);
+    std::string description = site_instance->GetSiteURL().spec();
+    if (site_instance->is_default_subframe_site_instance())
+      description = "default subframe process";
     base::StringAppendF(&result, "\n%s%s = %s", prefix,
-                        legend_entry.first.c_str(),
-                        site_instance->GetSiteURL().spec().c_str());
+                        legend_entry.first.c_str(), description.c_str());
     // Highlight some exceptionable conditions.
     if (site_instance->active_frame_count() == 0)
       result.append(" (active_frame_count == 0)");