Why this CL triggers an OilPan crash.

content/browser/renderer_host/render_view_host_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/renderer_host/render_view_host_impl.h"
 
 #include <set>
 #include <string>
 #include <utility>
 #include <vector>
@@ skipping 16 matching lines @@
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "cc/base/switches.h"
 #include "components/variations/variations_associated_data.h"
 #include "content/browser/bad_message.h"
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/dom_storage/session_storage_namespace_impl.h"
 #include "content/browser/frame_host/frame_tree.h"
+#include "content/browser/frame_host/render_frame_proxy_host.h"
 #include "content/browser/gpu/compositor_util.h"
 #include "content/browser/gpu/gpu_data_manager_impl.h"
 #include "content/browser/gpu/gpu_process_host.h"
 #include "content/browser/host_zoom_map_impl.h"
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/renderer_host/input/timeout_monitor.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_delegate.h"
 #include "content/browser/renderer_host/render_view_host_delegate_view.h"
 #include "content/browser/renderer_host/render_widget_host_delegate.h"
@@ skipping 250 matching lines @@
   params->main_frame_routing_id = main_frame_routing_id_;
   if (main_frame_routing_id_ != MSG_ROUTING_NONE) {
     RenderFrameHostImpl* main_rfh = RenderFrameHostImpl::FromID(
         GetProcess()->GetID(), main_frame_routing_id_);
     DCHECK(main_rfh);
     RenderWidgetHostImpl* main_rwh = main_rfh->GetRenderWidgetHost();
     params->main_frame_widget_routing_id = main_rwh->GetRoutingID();
   }
   params->session_storage_namespace_id =
       delegate_->GetSessionStorageNamespace(instance_.get())->id();
-  // Ensure the RenderView sets its opener correctly.
+  if (main_frame_routing_id_ != MSG_ROUTING_NONE) {
+    params->browsing_instance_id = RenderFrameHostImpl::FromID(
+        GetProcess()->GetID(), main_frame_routing_id_)
+          ->GetSiteInstance()
+          ->GetBrowsingInstanceId();
+  } else if (opener_frame_route_id != MSG_ROUTING_NONE) {
+    params->browsing_instance_id = RenderFrameHostImpl::FromID(
+        GetProcess()->GetID(), opener_frame_route_id)
+          ->GetSiteInstance()
+          ->GetBrowsingInstanceId();
+  } else if (proxy_route_id != MSG_ROUTING_NONE) {
+    SiteInstance* site_instance = RenderFrameProxyHost::FromID(
+        GetProcess()->GetID(), proxy_route_id)
+          ->GetSiteInstance();
+    params->browsing_instance_id = static_cast<SiteInstanceImpl*>(site_instance)
+          ->GetBrowsingInstanceId();
+  } else {
+    CHECK(false);
+    params->browsing_instance_id = -1;
+  }
   params->opener_frame_route_id = opener_frame_route_id;
   params->swapped_out = !is_active_;
   params->replicated_frame_state = replicated_frame_state;
   params->proxy_routing_id = proxy_route_id;
   params->hidden = is_active_ ? GetWidget()->is_hidden()
                               : GetWidget()->delegate()->IsHidden();
   params->never_visible = delegate_->IsNeverVisible();
   params->window_was_created_with_opener = window_was_created_with_opener;
   params->enable_auto_resize = GetWidget()->auto_resize_enabled();
   params->min_size = GetWidget()->min_size_for_auto_resize();
@@ skipping 641 matching lines @@
 }
 
 void RenderViewHostImpl::ClosePageTimeout() {
   if (delegate_->ShouldIgnoreUnresponsiveRenderer())
     return;
 
   ClosePageIgnoringUnloadEvents();
 }
 
 }  // namespace content