Deal with frame removal by content scripts

extensions/renderer/script_injection_manager.cc

Index: extensions/renderer/script_injection_manager.cc
diff --git a/extensions/renderer/script_injection_manager.cc b/extensions/renderer/script_injection_manager.cc
index aa0f5d32b9aa35ee7c4cbb85461f79899b169c6e..d8a24ba8fa9a5e6af5cf71886a6a2f2dbcf03055 100644
--- a/extensions/renderer/script_injection_manager.cc
+++ b/extensions/renderer/script_injection_manager.cc
@@ -162,7 +162,10 @@ void ScriptInjectionManager::RFOHelper::DidFailProvisionalLoad(
 
 void ScriptInjectionManager::RFOHelper::DidFinishDocumentLoad() {
   DCHECK(content::RenderThread::Get());
+  base::WeakPtr<RFOHelper> weak_self = weak_factory_.GetWeakPtr();
   manager_->StartInjectScripts(render_frame(), UserScript::DOCUMENT_END);
+  if (!weak_self.get())
+    return;
   // We try to run idle in two places: here and DidFinishLoad.
   // DidFinishDocumentLoad() corresponds to completing the document's load,
   // whereas DidFinishLoad corresponds to completing the document and all
@@ -172,8 +175,7 @@ void ScriptInjectionManager::RFOHelper::DidFinishDocumentLoad() {
   // triggered), then there's no reason to keep waiting.
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE,
-      base::Bind(&ScriptInjectionManager::RFOHelper::RunIdle,
-                 weak_factory_.GetWeakPtr()),
+      base::Bind(&ScriptInjectionManager::RFOHelper::RunIdle, weak_self),
       base::TimeDelta::FromMilliseconds(kScriptIdleTimeoutInMs));
 }