Require explicit selection of traits for LazyInstance

android_webview/native/aw_metrics_service_client_impl.h

 // Copyright 2017 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.
 
 #ifndef ANDROID_WEBVIEW_NATIVE_AW_METRICS_SERVICE_CLIENT_IMPL_
 #define ANDROID_WEBVIEW_NATIVE_AW_METRICS_SERVICE_CLIENT_IMPL_
 
 #include "android_webview/browser/aw_metrics_service_client.h"
 
 #include <jni.h>
 #include <string>
 
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "components/metrics/metrics_log_uploader.h"
 
 namespace metrics {
 class MetricsStateManager;
 }
 
 namespace android_webview {
 
 // This singleton manages metrics for an app using any number of WebViews. It
 // must always be used on the same thread. (Currently the UI thread is enforced,
 // but it could be any thread.) This is to prevent enable/disable race
 // conditions, and because MetricsService is single-threaded. Initialization is
 // asynchronous; even after Initialize has returned, some methods may not be
 // ready to use (see below).
 class AwMetricsServiceClientImpl : public AwMetricsServiceClient {
-  friend struct base::DefaultLazyInstanceTraits<AwMetricsServiceClientImpl>;
+  friend struct base::LazyInstanceTraitsBase<AwMetricsServiceClientImpl>;
 
  public:
   void Initialize(PrefService* pref_service,
                   net::URLRequestContextGetter* request_context,
                   const base::FilePath guid_file_path) override;
 
   // metrics::EnabledStateProvider implementation
   bool IsConsentGiven() override;
 
   // The below functions must not be called until initialization has
@@ skipping 32 matching lines @@
   std::unique_ptr<metrics::MetricsService> metrics_service_;
 
   DISALLOW_COPY_AND_ASSIGN(AwMetricsServiceClientImpl);
 };
 
 bool RegisterAwMetricsServiceClient(JNIEnv* env);
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_NATIVE_AW_METRICS_SERVICE_CLIENT_IMPL_