Ensure that the browser’s copy of page id is in sync with the renderer’s.

content/browser/web_contents/web_contents_impl.cc

 // Copyright (c) 2012 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/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
+#include "base/debug/crash_logging.h"
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/stats_counters.h"
 #include "base/process/process.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 3577 matching lines @@
   FOR_EACH_OBSERVER(WebContentsObserver,
                     observers_,
                     RenderProcessGone(GetCrashedStatus()));
 }
 
 void WebContentsImpl::RenderViewDeleted(RenderViewHost* rvh) {
   FOR_EACH_OBSERVER(WebContentsObserver, observers_, RenderViewDeleted(rvh));
 }
 
 void WebContentsImpl::UpdateState(RenderViewHost* rvh,
+                                  int32 rvh_page_id,
                                   int32 page_id,
                                   const PageState& page_state) {
+  if (rvh_page_id != page_id) {
+    base::debug::SetCrashKeyValue("renderer_page_id",
+                                  base::IntToString(page_id));
+    base::debug::SetCrashKeyValue("browser_page_id",
+                                  base::IntToString(rvh_page_id));
+    NavigationEntryImpl* entry = NavigationEntryImpl::FromNavigationEntry(
+        controller_.GetLastCommittedEntry());
+    // The question being answered here is: when there is a page id mismatch
+    // between the renderer and the browser, which value (if either) matches
+    // that of the last committed entry?
+    if (entry) {
+      if (entry->site_instance() == rvh->GetSiteInstance()) {
+        base::debug::SetCrashKeyValue("last_committed_page_id",
+                                      base::IntToString(entry->GetPageID()));
+      } else {
+        base::debug::SetCrashKeyValue("last_committed_page_id",
+                                      "site instance mismatch");
+      }
+    } else {
+      base::debug::SetCrashKeyValue("last_committed_page_id", "no entry");
+    }
+    CHECK(false);
+  }
+
   // Ensure that this state update comes from a RenderViewHost that belongs to
   // this WebContents.
   // TODO(nasko): This should go through RenderFrameHost.
   // TODO(creis): We can't update state for cross-process subframes until we
   // have FrameNavigationEntries.  Once we do, this should be a DCHECK.
   if (rvh->GetDelegate()->GetAsWebContents() != this)
     return;
 
   // We must be prepared to handle state updates for any page, these occur
   // when the user is scrolling and entering form data, as well as when we're
@@ skipping 736 matching lines @@
   node->render_manager()->ResumeResponseDeferredAtStart();
 }
 
 void WebContentsImpl::SetForceDisableOverscrollContent(bool force_disable) {
   force_disable_overscroll_content_ = force_disable;
   if (view_)
     view_->SetOverscrollControllerEnabled(CanOverscrollContent());
 }
 
 }  // namespace content