electron/patches/chromium/worker_context_will_destroy.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Cheng Zhao <zcbenz@gmail.com>
Date: Thu, 20 Sep 2018 17:47:12 -0700
Subject: worker_context_will_destroy.patch

This adds a hook for worker context destruction, which we use in Electron to
shutdown node integration in the worker if relevant.

An attempt to upstream this was made, but rejected:
https://chromium-review.googlesource.com/c/chromium/src/+/1954347

diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 42c94f71f09cf9067bac9fd9004dda36708ec441..07c014a28ed1ef5878a50fbb194e38fe762361e9 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -417,6 +417,11 @@ class CONTENT_EXPORT ContentRendererClient {
   virtual void DidInitializeWorkerContextOnWorkerThread(
       v8::Local<v8::Context> context) {}
 
+  // Notifies that a worker context will be destroyed. This function is called
+  // from the worker thread.
+  virtual void WillDestroyWorkerContextOnWorkerThread(
+      v8::Local<v8::Context> context) {}
+
   // Overwrites the given URL to use an HTML5 embed if possible.
   // An empty URL is returned if the URL is not overriden.
   virtual GURL OverrideFlashEmbedWithHTML(const GURL& url);
diff --git a/content/renderer/renderer_blink_platform_impl.cc b/content/renderer/renderer_blink_platform_impl.cc
index 24ed2d721fa6b261cc817c82ddf1d1ae0b5e82ed..86684e38d8cb84889c090576ab7f0f0e05b5c2b6 100644
--- a/content/renderer/renderer_blink_platform_impl.cc
+++ b/content/renderer/renderer_blink_platform_impl.cc
@@ -887,6 +887,12 @@ void RendererBlinkPlatformImpl::WillStopWorkerThread() {
   WorkerThreadRegistry::Instance()->WillStopCurrentWorkerThread();
 }
 
+void RendererBlinkPlatformImpl::WorkerContextWillDestroy(
+    const v8::Local<v8::Context>& worker) {
+  GetContentClient()->renderer()->WillDestroyWorkerContextOnWorkerThread(
+      worker);
+}
+
 void RendererBlinkPlatformImpl::WorkerContextCreated(
     const v8::Local<v8::Context>& worker) {
   GetContentClient()->renderer()->DidInitializeWorkerContextOnWorkerThread(
diff --git a/content/renderer/renderer_blink_platform_impl.h b/content/renderer/renderer_blink_platform_impl.h
index ced5bb344ec46e751ad8331242967e9b207bc572..54cebcbc49875287b5ae008b14e7df515f31a2d5 100644
--- a/content/renderer/renderer_blink_platform_impl.h
+++ b/content/renderer/renderer_blink_platform_impl.h
@@ -196,6 +196,7 @@ class CONTENT_EXPORT RendererBlinkPlatformImpl : public BlinkPlatformImpl {
   void DidStartWorkerThread() override;
   void WillStopWorkerThread() override;
   void WorkerContextCreated(const v8::Local<v8::Context>& worker) override;
+  void WorkerContextWillDestroy(const v8::Local<v8::Context>& worker) override;
   bool AllowScriptExtensionForServiceWorker(
       const blink::WebSecurityOrigin& script_origin) override;
   blink::ProtocolHandlerSecurityLevel GetProtocolHandlerSecurityLevel(
diff --git a/third_party/blink/public/platform/platform.h b/third_party/blink/public/platform/platform.h
index d4e60554211f1e7ef5455fb870284127281348b4..38c6e96ac42ff064cb337a4edb493ecf95bd6820 100644
--- a/third_party/blink/public/platform/platform.h
+++ b/third_party/blink/public/platform/platform.h
@@ -662,6 +662,7 @@ class BLINK_PLATFORM_EXPORT Platform {
   virtual void DidStartWorkerThread() {}
   virtual void WillStopWorkerThread() {}
   virtual void WorkerContextCreated(const v8::Local<v8::Context>& worker) {}
+  virtual void WorkerContextWillDestroy(const v8::Local<v8::Context>& worker) {}
   virtual bool AllowScriptExtensionForServiceWorker(
       const WebSecurityOrigin& script_origin) {
     return false;
diff --git a/third_party/blink/renderer/core/workers/worker_thread.cc b/third_party/blink/renderer/core/workers/worker_thread.cc
index 41729a86dab4be0350a4a935ae984c477304dfea..286a9aa7f8041d3be2c8675c6e5371de6a58af7f 100644
--- a/third_party/blink/renderer/core/workers/worker_thread.cc
+++ b/third_party/blink/renderer/core/workers/worker_thread.cc
@@ -762,6 +762,12 @@ void WorkerThread::PrepareForShutdownOnWorkerThread() {
   }
   pause_handle_.reset();
 
+  {
+    v8::HandleScope handle_scope(GetIsolate());
+    Platform::Current()->WorkerContextWillDestroy(
+        GlobalScope()->ScriptController()->GetContext());
+  }
+
   if (WorkerThreadDebugger* debugger = WorkerThreadDebugger::From(GetIsolate()))
     debugger->WorkerThreadDestroyed(this);