PageTransition: Remove unreached code.

content/renderer/render_frame_impl.cc

 // Copyright 2013 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 "content/renderer/render_frame_impl.h"
 
 #include <algorithm>
 #include <map>
 #include <string>
 #include <utility>
@@ skipping 4924 matching lines @@
       // This zoom level was merely recorded transiently for this load.  We can
       // erase it now.  If at some point we reload this page, the browser will
       // send us a new, up-to-date zoom level.
       host_zoom_levels_.erase(host_zoom);
     }
 
     // Update contents MIME type for main frame.
     params.contents_mime_type = ds->GetResponse().MimeType().Utf8();
 
     params.transition = navigation_state->GetTransitionType();
-    if (!ui::PageTransitionIsMainFrame(params.transition)) {
-      // If the main frame does a load, it should not be reported as a subframe
-      // navigation.  This can occur in the following case:
-      // 1. You're on a site with frames.
-      // 2. You do a subframe navigation.  This is stored with transition type
-      //    MANUAL_SUBFRAME.
-      // 3. You navigate to some non-frame site, say, google.com.
-      // 4. You navigate back to the page from step 2.  Since it was initially
-      //    MANUAL_SUBFRAME, it will be that same transition type here.
-      // We don't want that, because any navigation that changes the toplevel
-      // frame should be tracked as a toplevel navigation (this allows us to
-      // update the URL bar, etc).
-      params.transition = ui::PAGE_TRANSITION_LINK;
-    }
+    DCHECK(ui::PageTransitionIsMainFrame(params.transition));

[Avi (use Gerrit), 2017/06/28 17:03:18]

Just wow.

Hoping that this really does hold and we don't need that block.

 
     // If the page contained a client redirect (meta refresh, document.loc...),
     // set the transition appropriately.
     if (ds->IsClientRedirect()) {
       params.transition = ui::PageTransitionFromInt(
           params.transition | ui::PAGE_TRANSITION_CLIENT_REDIRECT);
     }
 
     // Send the user agent override back.
     params.is_overriding_user_agent = internal_data->is_overriding_user_agent();
@@ skipping 1924 matching lines @@
       replaces_current_history_item(info.replaces_current_history_item),
       history_navigation_in_new_child_frame(
           info.is_history_navigation_in_new_child_frame),
       client_redirect(info.is_client_redirect),
       triggering_event_info(info.triggering_event_info),
       cache_disabled(info.is_cache_disabled),
       form(info.form),
       source_location(info.source_location) {}
 
 }  // namespace content