Remove references to prerender and instant in content.

content/browser/tab_contents/tab_contents.cc

 // Copyright (c) 2011 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/tab_contents/tab_contents.h"
 
 #include <cmath>
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
@@ skipping 581 matching lines @@
 
   if (delegate_)
     delegate_->DidNavigateToPendingEntry(this);
 
   return true;
 }
 
 void TabContents::SetHistoryLengthAndPrune(const SiteInstance* site_instance,
                                            int history_length,
                                            int32 minimum_page_id) {
-  // SetHistoryLengthAndPrune doesn't handle pending cross-site navigations
-  // cleanly. Since it's only used when swapping in instant and prerendered
-  // TabContents, checks are done at a higher level to ensure that the pages
-  // are not swapped in during this case.
+  // SetHistoryLengthAndPrune doesn't work when there are pending cross-site
+  // navigations. Callers should ensure that this is the case.
   if (render_manager_.pending_render_view_host()) {
     NOTREACHED();
     return;
   }
   RenderViewHost* rvh = render_view_host();
   if (!rvh) {
     NOTREACHED();
     return;
   }
   if (site_instance && rvh->site_instance() != site_instance) {
@@ skipping 1321 matching lines @@
 }
 
 void TabContents::SwapInRenderViewHost(RenderViewHost* rvh) {
   render_manager_.SwapInRenderViewHost(rvh);
 }
 
 void TabContents::CreateViewAndSetSizeForRVH(RenderViewHost* rvh) {
   RenderWidgetHostView* rwh_view = view()->CreateViewForWidget(rvh);
   rwh_view->SetSize(view()->GetContainerSize());
 }