Support IPH NotifyEvent calls before Initialize

components/feature_engagement_tracker/internal/init_aware_model.h

Index: components/feature_engagement_tracker/internal/init_aware_model.h
diff --git a/components/feature_engagement_tracker/internal/init_aware_model.h b/components/feature_engagement_tracker/internal/init_aware_model.h
new file mode 100644
index 0000000000000000000000000000000000000000..72a76d1b91fe866e35373910b6504247cca7e3f4
--- /dev/null
+++ b/components/feature_engagement_tracker/internal/init_aware_model.h
@@ -0,0 +1,47 @@
+// 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 COMPONENTS_FEATURE_ENGAGEMENT_TRACKER_INTERNAL_INIT_AWARE_MODEL_H_
+#define COMPONENTS_FEATURE_ENGAGEMENT_TRACKER_INTERNAL_INIT_AWARE_MODEL_H_
+
+#include <stdint.h>
+
+#include <memory>
+#include <string>
+#include <tuple>
+#include <vector>
+
+#include "base/memory/weak_ptr.h"
+#include "components/feature_engagement_tracker/internal/model.h"
+
+namespace feature_engagement_tracker {
+
+class InitAwareModel : public Model {
+ public:
+  InitAwareModel(std::unique_ptr<Model> model);
+  ~InitAwareModel() override;
+
+  // Model implementation.
+  void Initialize(const OnModelInitializationFinished& callback,
+                  uint32_t current_day) override;
+  bool IsReady() const override;
+  const Event* GetEvent(const std::string& event_name) const override;
+  void IncrementEvent(const std::string& event_name,
+                      uint32_t current_day) override;
+
+ private:
+  void OnInitializeComplete(const OnModelInitializationFinished& callback,
+                            bool success);
+
+  std::unique_ptr<Model> model_;
+  std::vector<std::tuple<std::string, uint32_t>> queued_events_;
+
+  base::WeakPtrFactory<InitAwareModel> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(InitAwareModel);
+};
+
+}  // namespace feature_engagement_tracker
+
+#endif  // COMPONENTS_FEATURE_ENGAGEMENT_TRACKER_INTERNAL_INIT_AWARE_MODEL_H_