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chrome/browser/tab_contents/navigation_controller.cc

 // Copyright (c) 2010 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 "chrome/browser/tab_contents/navigation_controller.h"
 
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "base/time.h"
@@ skipping 968 matching lines @@
   // Take over the session id from source.
   session_id_ = source->session_id_;
 
   // Reset source's session id as we're taking it over. We give it a new id in
   // case source is added later on, which can happen with instant enabled if the
   // tab has a before unload handler.
   source->session_id_ = SessionID();
 }
 
 void NavigationController::PruneAllButActive() {
-  int prune_count = entry_count();
   if (transient_entry_index_ != -1) {
     // There is a transient entry. Prune up to it.
     DCHECK_EQ(entry_count() - 1, transient_entry_index_);
-    prune_count = transient_entry_index_;
+    entries_.erase(entries_.begin(), entries_.begin() + transient_entry_index_);
     transient_entry_index_ = 0;
     last_committed_entry_index_ = -1;
     pending_entry_index_ = -1;
   } else if (!pending_entry_) {
     // There's no pending entry. Leave the last entry (if there is one).
-    if (!prune_count)
+    if (!entry_count())
       return;
 
-    prune_count--;
+    DCHECK(last_committed_entry_index_ >= 0);
+    entries_.erase(entries_.begin(),
+                   entries_.begin() + last_committed_entry_index_);
+    entries_.erase(entries_.begin() + 1, entries_.end());
     last_committed_entry_index_ = 0;
   } else if (pending_entry_index_ != -1) {
-    DCHECK_EQ(pending_entry_index_, prune_count - 1);
+    entries_.erase(entries_.begin(), entries_.begin() + pending_entry_index_);
+    entries_.erase(entries_.begin() + 1, entries_.end());
     pending_entry_index_ = 0;
     last_committed_entry_index_ = 0;
-    prune_count--;
   } else {
     // There is a pending_entry, but it's not in entries_.
     pending_entry_index_ = -1;
     last_committed_entry_index_ = -1;
+    entries_.clear();
   }
 
   if (tab_contents_->interstitial_page()) {
     // Normally the interstitial page hides itself if the user doesn't proceeed.
     // This would result in showing a NavigationEntry we just removed. Set this
     // so the interstitial triggers a reload if the user doesn't proceed.
     tab_contents_->interstitial_page()->set_reload_on_dont_proceed(true);
   }
-
-  entries_.erase(entries_.begin(), entries_.begin() + prune_count);
 }
 
 void NavigationController::DiscardNonCommittedEntries() {
   bool transient = transient_entry_index_ != -1;
   DiscardNonCommittedEntriesInternal();
 
   // If there was a transient entry, invalidate everything so the new active
   // entry state is shown.
   if (transient) {
     tab_contents_->NotifyNavigationStateChanged(kInvalidateAllButShelves);
@@ skipping 168 matching lines @@
   size_t insert_index = 0;
   for (int i = 0; i < max_index; i++) {
     // When cloning a tab, copy all entries except interstitial pages
     if (source.entries_[i].get()->page_type() != INTERSTITIAL_PAGE) {
       entries_.insert(entries_.begin() + insert_index++,
                       linked_ptr<NavigationEntry>(
                           new NavigationEntry(*source.entries_[i])));
     }
   }
 }