Remove deprecated navigation callbacks on WebContentsObserver that are now unused.

content/browser/frame_host/navigator_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/browser/frame_host/navigator_impl.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 174 matching lines @@
       !policy->IsWebSafeScheme(validated_url.scheme())) {
     validated_url = GURL(url::kAboutBlankURL);
   }
 
   if (is_main_frame && !is_error_page) {
     DidStartMainFrameNavigation(validated_url,
                                 render_frame_host->GetSiteInstance(),
                                 render_frame_host->navigation_handle());
   }
 
-  if (delegate_) {
-    // Notify the observer about the start of the provisional load.
-    delegate_->DidStartProvisionalLoad(render_frame_host, validated_url,
-                                       is_error_page);
-  }
-
   if (is_error_page || IsBrowserSideNavigationEnabled())
     return;
 
   if (render_frame_host->navigation_handle()) {
     if (render_frame_host->navigation_handle()->is_transferring()) {
       // If the navigation is completing a transfer, this
       // DidStartProvisionalLoad should not correspond to a new navigation.
       DCHECK_EQ(url, render_frame_host->navigation_handle()->GetURL());
       render_frame_host->navigation_handle()->set_is_transferring(false);
       return;
@@ skipping 480 matching lines @@
   // After setting the last committed origin, reset the feature policy in the
   // RenderFrameHost to a blank policy based on the parent frame.
   render_frame_host->ResetFeaturePolicy();
 
   // Send notification about committed provisional loads. This notification is
   // different from the NAV_ENTRY_COMMITTED notification which doesn't include
   // the actual URL navigated to and isn't sent for AUTO_SUBFRAME navigations.
   if (details.type != NAVIGATION_TYPE_NAV_IGNORE && delegate_) {
     DCHECK_EQ(!render_frame_host->GetParent(),
               did_navigate ? details.is_main_frame : false);
-    ui::PageTransition transition_type = params.transition;
-    // Whether or not a page transition was triggered by going backward or
-    // forward in the history is only stored in the navigation controller's
-    // entry list.
-    if (did_navigate &&
-        (controller_->GetLastCommittedEntry()->GetTransitionType() &
-            ui::PAGE_TRANSITION_FORWARD_BACK)) {
-      transition_type = ui::PageTransitionFromInt(
-          params.transition | ui::PAGE_TRANSITION_FORWARD_BACK);

[nasko, 2017/02/10 19:44:58]

Hmm, I wonder if we have a discrepancy between the transition type on the
NavigationHandle and this one. Do you think temporarily leaving this and having
a DCHECK that the types here and in the NavigationHandle match?

[jam, 2017/02/10 20:00:34]

Given that no tests failed, I'm not inclined to have code to check the old and
new code paths.

-    }
-
-    delegate_->DidCommitProvisionalLoad(render_frame_host,
-                                        params.url,
-                                        transition_type);
     navigation_handle->DidCommitNavigation(params, details.did_replace_entry,
                                            details.previous_url, details.type,
                                            render_frame_host);
     navigation_handle.reset();
   }
 
   if (!did_navigate)
     return;  // No navigation happened.
 
   // DO NOT ADD MORE STUFF TO THIS FUNCTION! Your component should either listen
@@ skipping 600 matching lines @@
     if (navigation_handle)
       navigation_handle->update_entry_id_for_transfer(entry->GetUniqueID());
 
     controller_->SetPendingEntry(std::move(entry));
     if (delegate_)
       delegate_->NotifyChangedNavigationState(content::INVALIDATE_TYPE_URL);
   }
 }
 
 }  // namespace content