In --site-per-process, don't try to call beforeunload on subframes yet.

content/browser/frame_host/render_frame_host_manager.cc

Index: content/browser/frame_host/render_frame_host_manager.cc
diff --git a/content/browser/frame_host/render_frame_host_manager.cc b/content/browser/frame_host/render_frame_host_manager.cc
index d697e186d0c4dae004a901635c31d549514bffb9..3031266d732a1ac9b25e92012d1146e45bb228fe 100644
--- a/content/browser/frame_host/render_frame_host_manager.cc
+++ b/content/browser/frame_host/render_frame_host_manager.cc
@@ -408,18 +408,18 @@ void RenderFrameHostManager::SwappedOutFrame(
     return;
   }
 
-  // Sanity check that this is for the correct frame.
-  DCHECK_EQ(render_frame_host_->GetRoutingID(),
-            pending_nav_params_->render_frame_id);
-  DCHECK_EQ(render_frame_host_->GetProcess()->GetID(),
-            pending_nav_params_->global_request_id.child_id);
-
   // Now that the unload handler has run, we need to either initiate the
   // pending transfer (if there is one) or resume the paused response (if not).
   // TODO(creis): The blank swapped out page is visible during this time, but
   // we can shorten this by delivering the response directly, rather than
   // forcing an identical request to be made.
   if (pending_nav_params_->cross_site_transferring_request) {
+    // Sanity check that this is for the correct frame.

[Charlie Reis, 2014/03/21 23:24:33]

This check only makes sense for transfers, not browser-initiated navigations
(like I've just made possible in the test).

+    DCHECK_EQ(render_frame_host_->GetRoutingID(),
+              pending_nav_params_->render_frame_id);
+    DCHECK_EQ(render_frame_host_->GetProcess()->GetID(),
+              pending_nav_params_->global_request_id.child_id);
+
     // Treat the last URL in the chain as the destination and the remainder as
     // the redirect chain.
     CHECK(pending_nav_params_->transfer_url_chain.size());
@@ -1311,8 +1311,12 @@ RenderFrameHostImpl* RenderFrameHostManager::UpdateRendererStateForNavigate(
       render_frame_host_->render_view_host()->Send(new ViewMsg_Stop(
           render_frame_host_->render_view_host()->GetRoutingID()));
 
-      pending_render_frame_host_->render_view_host()->SetNavigationsSuspended(
-          true, base::TimeTicks());
+      // TODO(creis): Skip this for subframes until we can run beforeunload
+      // handlers on them.
+      if (frame_tree_node_->IsMainFrame()) {
+        pending_render_frame_host_->render_view_host()->SetNavigationsSuspended(
+            true, base::TimeTicks());
+      }
 
       // Tell the CrossSiteRequestManager that this RVH has a pending cross-site
       // request, so that ResourceDispatcherHost will know to tell us to run the
@@ -1330,7 +1334,8 @@ RenderFrameHostImpl* RenderFrameHostManager::UpdateRendererStateForNavigate(
     // tell the old render view to run its beforeunload handler, since it
     // doesn't otherwise know that the cross-site request is happening.  This
     // will trigger a call to OnBeforeUnloadACK with the reply.
-    if (!is_transfer)
+    // TODO(creis): Support beforeunload on subframes.
+    if (!is_transfer && frame_tree_node_->IsMainFrame())
       render_frame_host_->DispatchBeforeUnload(true);
 
     return pending_render_frame_host_.get();