From a513e01b01497178672845ea1ed8f6ce90d4f5c9 Mon Sep 17 00:00:00 2001
From: Marshall Greenblatt <magreenblatt@gmail.com>
Date: Wed, 9 Mar 2022 13:13:45 -0500
Subject: [PATCH] Fix shutdown crash in RenderProcessHostImpl::Cleanup (fixes
 issue #3276)

Execute all pending UI thread tasks at the beginning of the shutdown sequence.
---
 libcef/browser/main_runner.cc | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/libcef/browser/main_runner.cc b/libcef/browser/main_runner.cc
index f5fbb19de..d4284ee6c 100644
--- a/libcef/browser/main_runner.cc
+++ b/libcef/browser/main_runner.cc
@@ -482,6 +482,16 @@ void CefMainRunner::FinishShutdownOnUIThread(
     base::WaitableEvent* uithread_shutdown_event) {
   CEF_REQUIRE_UIT();
 
+  // Execute all pending tasks now before proceeding with shutdown. Otherwise,
+  // objects bound to tasks and released at the end of shutdown via
+  // BrowserTaskExecutor::Shutdown may attempt to access other objects that have
+  // already been destroyed (for example, if teardown results in a call to
+  // RenderProcessHostImpl::Cleanup).
+  content::BrowserTaskExecutor::RunAllPendingTasksOnThreadForTesting(
+      content::BrowserThread::UI);
+  content::BrowserTaskExecutor::RunAllPendingTasksOnThreadForTesting(
+      content::BrowserThread::IO);
+
   static_cast<content::ContentMainRunnerImpl*>(main_runner_.get())
       ->ShutdownOnUIThread();