Omnibox UI Experiments: Enable trimming of trivial subdomains.

components/omnibox/browser/autocomplete_match.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/omnibox/browser/autocomplete_match.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/feature_list.h"
@@ skipping 508 matching lines @@
         base::LimitOffset<std::string>(format_url_return_value.length()));
   }
   return format_url_return_value;
 }
 
 // static
 base::string16 AutocompleteMatch::FormatUrlForSuggestionDisplayWithAdjustments(
     const GURL& url,
     bool trim_scheme,
     base::OffsetAdjuster::Adjustments* adjustments) {
+  GURL trimmed_url = url;
+
+  // Trim off trivial subdomains if experiment is enabled.
+  if (base::FeatureList::IsEnabled(
+          omnibox::kUIExperimentHideSuggestionUrlTrivialSubdomains)) {
+    GURL::Replacements replacements;
+    replacements.SetHostStr(url_formatter::StripSubdomains(
+        url, url_formatter::kStripWWW | url_formatter::kStripM));
+    trimmed_url = url.ReplaceComponents(replacements);
+  }

[tommycli, 2017/06/23 00:10:54]

This pattern now makes me feel that the smart thing to do for scheme trimming is
basically: if (trim_scheme and feature enabled and scheme is HTTPS) replace
scheme with HTTP and allow url_formatter to trim that off.

If you agree I can followup and do that...

[Justin Donnelly, 2017/06/23 15:12:25]

That's both an elegant solution to the code duplication and also feels like a
weird hack. :) I'm inclined to stick with what you have here and just do the
right thing (put it in url_formatter and/or refactor as pkasting suggested) if
and when we decide it's permanent.

[tommycli, 2017/06/23 18:23:05]

Gotcha, alright good to hear my first instinct was the correct one then. :)

+
   const url_formatter::FormatUrlTypes format_types =
       url_formatter::kFormatUrlOmitAll &
       ~(trim_scheme ? 0 : url_formatter::kFormatUrlOmitHTTP);
   base::string16 result = url_formatter::FormatUrlWithAdjustments(
-      url, format_types, net::UnescapeRule::SPACES, nullptr, nullptr,
+      trimmed_url, format_types, net::UnescapeRule::SPACES, nullptr, nullptr,
       adjustments);
 
   // Also trim HTTPS if experiment is enabled. Note this intentionally has
   // no effect on view-source URLs.
   if (trim_scheme && base::FeatureList::IsEnabled(
                          omnibox::kUIExperimentHideSuggestionUrlScheme)) {
     // TODO(tommycli): If this becomes enabled by default, investigate
     // folding this logic into url_formatter::FormatUrlWithAdjustments.
     if (url.SchemeIs(url::kHttpsScheme)) {
       const size_t kHTTPSSize =
@@ skipping 145 matching lines @@
         << " is unsorted in relation to last offset of " << last_offset
         << ". Provider: " << provider_name << ".";
     DCHECK_LT(i->offset, text.length())
         << " Classification of [" << i->offset << "," << text.length()
         << "] is out of bounds for \"" << text << "\". Provider: "
         << provider_name << ".";
     last_offset = i->offset;
   }
 }
 #endif