Don't leave renderer process frozen when canceling JavaScript dialogs.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index ffcc72b3b8dca97981cebe899e4becc36b3ac48b..8712acdd6f84f7e424ec019701384fdc854d24a7 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -3666,6 +3666,13 @@ void WebContentsImpl::UpdateRenderViewSizeForRenderManager() {
     view_->SizeContents(size);
 }
 
+void WebContentsImpl::CancelModalDialogsForRenderManager() {
+  // We need to cancel modal dialogs when doing a process swap, since the load
+  // deferrer would prevent us from swapping out.
+  if (dialog_manager_)
+    dialog_manager_->CancelActiveAndPendingDialogs(this);
+}
+
 void WebContentsImpl::NotifySwappedFromRenderManager(RenderViewHost* rvh) {
   NotifySwapped(rvh);