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..ad387a2b257cd6afca971c5fd572f43426a16588 100644
--- a/extensions/renderer/script_injection_manager.cc
+++ b/extensions/renderer/script_injection_manager.cc
@@ -27,6 +27,7 @@
 #include "ipc/ipc_message_macros.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebFrame.h"
+#include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebView.h"
 #include "url/gurl.h"
@@ -67,6 +68,8 @@ class ScriptInjectionManager::RFOHelper : public content::RenderFrameObserver {
   ~RFOHelper() override;
 
  private:
+  class ScheduledScriptInjection;
+
   // RenderFrameObserver implementation.
   bool OnMessageReceived(const IPC::Message& message) override;
   void DidCreateNewDocument() override;
@@ -111,6 +114,39 @@ ScriptInjectionManager::RFOHelper::RFOHelper(content::RenderFrame* render_frame,
 ScriptInjectionManager::RFOHelper::~RFOHelper() {
 }
 
+// This class schedules a script injection at |run_location| in the frame.
+class ScriptInjectionManager::RFOHelper::ScheduledScriptInjection {
+ public:
+  ScheduledScriptInjection(base::WeakPtr<RFOHelper> rfo_helper_weak,
+                           UserScript::RunLocation run_location)
+      : rfo_helper_weak_(rfo_helper_weak), run_location_(run_location) {
+    v8::Isolate* isolate = blink::mainThreadIsolate();
+    isolate->EnqueueMicrotask(RunScheduledScriptInjection, this);
+  }
+
+ private:
+  // This is called once when V8 runs the microtask.
+  static void RunScheduledScriptInjection(void* data) {
+    ScheduledScriptInjection* scheduled_script_injection =
+        static_cast<ScheduledScriptInjection*>(data);
+    scheduled_script_injection->StartInjectScripts();
+    delete scheduled_script_injection;
+  }
+
+  void StartInjectScripts() {
+    RFOHelper* rfo_helper = rfo_helper_weak_.get();
+    if (!rfo_helper)
+      return;
+    rfo_helper->manager_->StartInjectScripts(rfo_helper->render_frame(),
+                                             run_location_);
+  }
+
+  base::WeakPtr<RFOHelper> rfo_helper_weak_;
+  UserScript::RunLocation run_location_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScheduledScriptInjection);
+};
+
 bool ScriptInjectionManager::RFOHelper::OnMessageReceived(
     const IPC::Message& message) {
   bool handled = true;
@@ -136,7 +172,8 @@ void ScriptInjectionManager::RFOHelper::DidCreateNewDocument() {
 }
 
 void ScriptInjectionManager::RFOHelper::DidCreateDocumentElement() {
-  manager_->StartInjectScripts(render_frame(), UserScript::DOCUMENT_START);
+  new ScheduledScriptInjection(
+      weak_factory_.GetWeakPtr(), UserScript::DOCUMENT_START);
 }
 
 void ScriptInjectionManager::RFOHelper::DidFailProvisionalLoad(
@@ -162,7 +199,9 @@ void ScriptInjectionManager::RFOHelper::DidFailProvisionalLoad(
 
 void ScriptInjectionManager::RFOHelper::DidFinishDocumentLoad() {
   DCHECK(content::RenderThread::Get());
-  manager_->StartInjectScripts(render_frame(), UserScript::DOCUMENT_END);
+  new ScheduledScriptInjection(
+      weak_factory_.GetWeakPtr(), UserScript::DOCUMENT_END);
+
   // 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
@@ -227,7 +266,8 @@ void ScriptInjectionManager::RFOHelper::RunIdle() {
   // had idle run since the task to RunIdle() was posted.
   if (should_run_idle_) {
     should_run_idle_ = false;
-    manager_->StartInjectScripts(render_frame(), UserScript::DOCUMENT_IDLE);
+    new ScheduledScriptInjection(
+        weak_factory_.GetWeakPtr(), UserScript::DOCUMENT_IDLE);
   }
 }