Dying RenderProcessHostImpls should not send observer notifications.

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index a7141e4fc77eff52db504473ea70d0c81cd4cf30..6abd214cd56d4b9f94b4d96213c65a38639fc1a0 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -2320,6 +2320,12 @@ void RenderProcessHostImpl::OnProcessLaunched() {
 }
 
 void RenderProcessHostImpl::OnProcessLaunchFailed() {
+  // If this object will be destructed soon, then observers have already been
+  // sent a RenderProcessHostDestroyed notification, and we must observe our
+  // contract that says that will be the last call.
+  if (deleting_soon_)
+    return;
+
   RendererClosedDetails details { base::TERMINATION_STATUS_PROCESS_WAS_KILLED,
                                   -1 };
   ProcessDied(true, &details);