Avoid retaining the pointer to inspected WebContents in DevToolsWindow

content/browser/devtools/render_view_devtools_agent_host.cc

Index: content/browser/devtools/render_view_devtools_agent_host.cc
diff --git a/content/browser/devtools/render_view_devtools_agent_host.cc b/content/browser/devtools/render_view_devtools_agent_host.cc
index 26b14bf59886f502c74ddf9c310cb7fc4b9cbcb5..a0d9bccdc89a9ba84ea30651a016716aab96ca07 100644
--- a/content/browser/devtools/render_view_devtools_agent_host.cc
+++ b/content/browser/devtools/render_view_devtools_agent_host.cc
@@ -166,6 +166,8 @@ void RenderViewDevToolsAgentHost::DispatchOnInspectorBackend(
 }
 
 void RenderViewDevToolsAgentHost::SendMessageToAgent(IPC::Message* msg) {
+  if (!render_view_host_)
+    return;
   msg->set_routing_id(render_view_host_->GetRoutingID());
   render_view_host_->Send(msg);
 }