Fix bug in shut down of HTMLViewer

components/html_viewer/global_state.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/html_viewer/global_state.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 54 matching lines @@
       device_pixel_ratio_(1.f),
       discardable_memory_allocator_(kDesiredMaxMemory),
       compositor_thread_("compositor thread") {
 }
 
 GlobalState::~GlobalState() {
   if (blink_platform_) {
     renderer_scheduler_->Shutdown();
     blink::shutdown();
   }
+#if defined(OS_LINUX) && !defined(OS_ANDROID)
+  if (font_loader_.get()) {
+    SkFontConfigInterface::SetGlobal(nullptr);
+    // FontLoader is ref counted. We need to explicitly shutdown the background
+    // thread, otherwise the background thread may be shutdown after the app is
+    // torn down, when we're in a bad state.
+    font_loader_->Shutdown();
+  }
+#endif
 }
 
 void GlobalState::InitIfNecessary(const gfx::Size& screen_size_in_pixels,
                                   float device_pixel_ratio) {
   if (did_init_)
     return;
 
   DCHECK_NE(0.f, device_pixel_ratio);
 
   did_init_ = true;
   device_pixel_ratio_ = device_pixel_ratio;
   screen_size_in_pixels_ = screen_size_in_pixels;
 
   if (!resource_loader_.BlockUntilLoaded()) {
     // Assume on error we're being shut down.
     app_->Quit();
     return;
   }
 
 #if defined(OS_LINUX) && !defined(OS_ANDROID)
-  SkFontConfigInterface::SetGlobal(new font_service::FontLoader(app_));
+  font_loader_ = skia::AdoptRef(new font_service::FontLoader(app_));
+  SkFontConfigInterface::SetGlobal(font_loader_.get());
 #endif
 
   ui_init_.reset(
       new ui::mojo::UIInit(screen_size_in_pixels, device_pixel_ratio));
   base::DiscardableMemoryAllocator::SetInstance(&discardable_memory_allocator_);
 
   renderer_scheduler_ = scheduler::RendererScheduler::Create();
   blink_platform_.reset(new BlinkPlatformImpl(app_, renderer_scheduler_.get()));
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
   gin::V8Initializer::LoadV8SnapshotFromFD(
@@ skipping 30 matching lines @@
   media_factory_.reset(
       new MediaFactory(compositor_thread_.task_runner(), app_->shell()));
 
   if (command_line->HasSwitch(kJavaScriptFlags)) {
     std::string flags(command_line->GetSwitchValueASCII(kJavaScriptFlags));
     v8::V8::SetFlagsFromString(flags.c_str(), static_cast<int>(flags.size()));
   }
 }
 
 }  // namespace html_viewer