Windows: Fix AtExitManager assertions on shutdown when running with multi-threaded message loop (issue #1680)

libcef/browser/context.cc

@@ -420,6 +420,9 @@ void CefContext::FinishShutdownOnUIThread(
   if (trace_subscriber_.get())
     trace_subscriber_.reset(NULL);
 
+  if (component_updater_.get())
+    component_updater_.reset(NULL);
+
   if (uithread_shutdown_event)
     uithread_shutdown_event->Signal();
 }

patch/patch.cfg

@@ -141,6 +141,13 @@ patches = [
     'name': 'spellcheck_137',
     'path': '../chrome/browser/spellchecker/',
   },
+  {
+    # Fix AtExitManager assertion on PrefWatcherFactory destruction during
+    # Windows multi-threaded message loop shutdown.
+    # https://bitbucket.org/chromiumembedded/cef/issues/1680
+    'name': 'prefs_tab_helper_1680',
+    'path': '../chrome/browser/ui/prefs/',
+  },
   {
     # Make URLRequest::set_is_pending() public so that it can be called from
     # CefRequestInterceptor::MaybeInterceptResponse().

patch/patches/prefs_tab_helper_1680.patch

@@ -0,0 +1,47 @@
+diff --git prefs_tab_helper.cc prefs_tab_helper.cc
+index 5cb2d6e..b0c8689 100644
+--- prefs_tab_helper.cc
++++ prefs_tab_helper.cc
+@@ -7,7 +7,7 @@
+ #include <set>
+ #include <string>
+ 
+-#include "base/memory/singleton.h"
++#include "base/lazy_instance.h"
+ #include "base/prefs/overlay_user_pref_store.h"
+ #include "base/prefs/pref_change_registrar.h"
+ #include "base/prefs/pref_service.h"
+@@ -413,12 +413,10 @@ class PrefWatcherFactory : public BrowserContextKeyedServiceFactory {
+         GetInstance()->GetServiceForBrowserContext(profile, true));
+   }
+ 
+-  static PrefWatcherFactory* GetInstance() {
+-    return base::Singleton<PrefWatcherFactory>::get();
+-  }
++  static PrefWatcherFactory* GetInstance();
+ 
+  private:
+-  friend struct base::DefaultSingletonTraits<PrefWatcherFactory>;
++  friend struct base::DefaultLazyInstanceTraits<PrefWatcherFactory>;
+ 
+   PrefWatcherFactory() : BrowserContextKeyedServiceFactory(
+       "PrefWatcher",
+@@ -439,6 +437,18 @@ class PrefWatcherFactory : public BrowserContextKeyedServiceFactory {
+   }
+ };
+ 
++namespace {
++
++base::LazyInstance<PrefWatcherFactory>::Leaky g_pref_watcher_factory =
++    LAZY_INSTANCE_INITIALIZER;
++
++}  // namespace
++
++// static
++PrefWatcherFactory* PrefWatcherFactory::GetInstance() {
++  return g_pref_watcher_factory.Pointer();
++}
++
+ // static
+ PrefWatcher* PrefWatcher::Get(Profile* profile) {
+   return PrefWatcherFactory::GetForProfile(profile);