Remove uses of base/lazy_instance

shell/context.cc

 // Copyright 2013 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 "shell/context.h"
 
 #include <vector>
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
-#include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/path_service.h"
 #include "base/run_loop.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 #include "mojo/common/trace_provider_impl.h"
@@ skipping 21 matching lines @@
 #if !defined(OS_MACOSX)
 #include "shell/url_response_disk_cache_loader.h"
 #endif
 
 using mojo::ServiceProvider;
 using mojo::ServiceProviderPtr;
 
 namespace shell {
 namespace {
 
-// Used to ensure we only init once.
-class Setup {
- public:
-  Setup() {
-    mojo::embedder::Init(mojo::embedder::CreateSimplePlatformSupport());
-  }
-
-  ~Setup() {}
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(Setup);
-};
-
 ApplicationManager::Options MakeApplicationManagerOptions() {
   ApplicationManager::Options options;
   options.disable_cache = base::CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kDisableCache);
   options.force_offline_by_default =
       base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kForceOfflineByDefault);
   return options;
 }
 
@@ skipping 167 matching lines @@
   PathService::Get(base::DIR_CURRENT, &cwd);
   SetCommandLineCWD(cwd);
 }
 
 Context::~Context() {
   DCHECK(!base::MessageLoop::current());
 }
 
 // static
 void Context::EnsureEmbedderIsInitialized() {
-  static base::LazyInstance<Setup>::Leaky setup = LAZY_INSTANCE_INITIALIZER;
-  setup.Get();
+  static bool initialized = ([]() {
+    mojo::embedder::Init(mojo::embedder::CreateSimplePlatformSupport());
+    return true;
+  })();
+  std::ignore = initialized;

[jamesr, 2016/02/10 21:28:39]

arguably this is too fancy, especially since it comes from <tuple>.  if you
don't like it i can do "static_cast<void>(initialized);" here instead. there's a
debate about this very thing on the internal c++ style list

[viettrungluu, 2016/02/10 23:55:50]

Should probably use MOJO_ALLOW_UNUSED_LOCAL from mojo/public/c/system/macros.h.

Or maybe for consistency, ALLOW_UNUSED_LOCAL from base/compiler_specific.h.

 }
 
 void Context::SetShellFileRoot(const base::FilePath& path) {
   shell_file_root_ = AddTrailingSlashIfNeeded(FilePathToFileURL(path));
 }
 
 GURL Context::ResolveShellFileURL(const std::string& path) {
   return shell_file_root_.Resolve(path);
 }
 
@@ skipping 129 matching lines @@
   if (app_urls_.find(url) != app_urls_.end()) {
     app_urls_.erase(url);
     if (app_urls_.empty() && base::MessageLoop::current()->is_running()) {
       DCHECK(task_runners_->shell_runner()->RunsTasksOnCurrentThread());
       base::MessageLoop::current()->Quit();
     }
   }
 }
 
 }  // namespace shell