src/patch/patches/content_app_shutdown_2798.patch

diff --git content/app/content_main_runner_impl.cc content/app/content_main_runner_impl.cc
index bb72915a26e2..9fbafc0643e1 100644
--- content/app/content_main_runner_impl.cc
+++ content/app/content_main_runner_impl.cc
@@ -44,6 +44,7 @@
 #include "base/strings/stringprintf.h"
 #include "base/task/post_task.h"
 #include "base/task/thread_pool/thread_pool_instance.h"
+#include "base/threading/thread_restrictions.h"
 #include "base/trace_event/trace_event.h"
 #include "components/discardable_memory/service/discardable_shared_memory_manager.h"
 #include "components/download/public/common/download_task_runner.h"
@@ -1016,6 +1017,11 @@ void ContentMainRunnerImpl::Shutdown() {
   is_shutdown_ = true;
 }
 
+void ContentMainRunnerImpl::ShutdownOnUIThread() {
+  base::ScopedAllowBaseSyncPrimitivesForTesting allow_wait;
+  discardable_shared_memory_manager_.reset();
+}
+
 // static
 ContentMainRunner* ContentMainRunner::Create() {
   return ContentMainRunnerImpl::Create();
diff --git content/app/content_main_runner_impl.h content/app/content_main_runner_impl.h
index 4632e35eaf65..c74d9ca750c7 100644
--- content/app/content_main_runner_impl.h
+++ content/app/content_main_runner_impl.h
@@ -51,6 +51,8 @@ class ContentMainRunnerImpl : public ContentMainRunner {
   int Run(bool start_service_manager_only) override;
   void Shutdown() override;
 
+  void ShutdownOnUIThread();
+
  private:
 #if !defined(CHROME_MULTIPLE_DLL_CHILD)
   int RunServiceManager(MainFunctionParams& main_function_params,
diff --git content/app/content_service_manager_main_delegate.cc content/app/content_service_manager_main_delegate.cc
index 86d0a470a7c2..5e4b91d31e3f 100644
--- content/app/content_service_manager_main_delegate.cc
+++ content/app/content_service_manager_main_delegate.cc
@@ -130,4 +130,8 @@ void ContentServiceManagerMainDelegate::SetStartServiceManagerOnly(
   start_service_manager_only_ = start_service_manager_only;
 }
 
+void ContentServiceManagerMainDelegate::ShutdownOnUIThread() {
+  content_main_runner_->ShutdownOnUIThread();
+}
+
 }  // namespace content
diff --git content/app/content_service_manager_main_delegate.h content/app/content_service_manager_main_delegate.h
index 0b4042aec2ae..b8643b10a02e 100644
--- content/app/content_service_manager_main_delegate.h
+++ content/app/content_service_manager_main_delegate.h
@@ -18,7 +18,8 @@ namespace content {
 
 class ContentMainRunnerImpl;
 
-class ContentServiceManagerMainDelegate : public service_manager::MainDelegate {
+class CONTENT_EXPORT ContentServiceManagerMainDelegate :
+    public service_manager::MainDelegate {
  public:
   explicit ContentServiceManagerMainDelegate(const ContentMainParams& params);
   ~ContentServiceManagerMainDelegate() override;
@@ -46,6 +47,8 @@ class ContentServiceManagerMainDelegate : public service_manager::MainDelegate {
   // full browser.
   void SetStartServiceManagerOnly(bool start_service_manager_only);
 
+  void ShutdownOnUIThread();
+
  private:
   ContentMainParams content_main_params_;
   std::unique_ptr<ContentMainRunnerImpl> content_main_runner_;