Add the future storage framework for the BudgetDatabase.

chrome/browser/budget_service/budget_database.cc

Index: chrome/browser/budget_service/budget_database.cc
diff --git a/chrome/browser/budget_service/budget_database.cc b/chrome/browser/budget_service/budget_database.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f7d15397b69e8ae8e7056f6e8588b48241f3e0e9
--- /dev/null
+++ b/chrome/browser/budget_service/budget_database.cc
@@ -0,0 +1,55 @@
+// Copyright 2016 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 "chrome/browser/budget_service/budget_database.h"
+
+#include "chrome/browser/budget_service/budget.pb.h"
+#include "components/leveldb_proto/proto_database_impl.h"
+#include "content/public/browser/browser_thread.h"
+
+namespace {
+
+// UMA are logged for the database with this string as part of the name.
+// They will be LevelDB.*.BackgroundBudgetService. Changes here should be
+// synchronized with histograms.xml.
+const char kDatabaseUMAName[] = "BackgroundBudgetService";
+
+}  // namespace
+
+BudgetDatabase::BudgetDatabase(
+    const base::FilePath& database_dir,
+    const scoped_refptr<base::SequencedTaskRunner>& task_runner)
+    : db_(new leveldb_proto::ProtoDatabaseImpl<budget_service::Budget>(
+          task_runner)),
+      weak_ptr_factory_(this) {
+  db_->Init(kDatabaseUMAName, database_dir,
+            base::Bind(&BudgetDatabase::OnDatabaseInit,
+                       weak_ptr_factory_.GetWeakPtr()));
+}
+
+BudgetDatabase::~BudgetDatabase() {}
+
+void BudgetDatabase::OnDatabaseInit(bool success) {
+  // TODO(harkness): Consider caching the budget database now?
+}
+
+void BudgetDatabase::GetValue(const GURL& origin,
+                              const GetValueCallback& callback) {
+  DCHECK_EQ(origin.GetOrigin(), origin);
+  db_->GetEntry(origin.spec(), callback);
+}
+
+void BudgetDatabase::SetValue(const GURL& origin,
+                              const budget_service::Budget& budget,
+                              const SetValueCallback& callback) {
+  DCHECK_EQ(origin.GetOrigin(), origin);
+  std::unique_ptr<
+      leveldb_proto::ProtoDatabase<budget_service::Budget>::KeyEntryVector>
+      entries(new leveldb_proto::ProtoDatabase<
+              budget_service::Budget>::KeyEntryVector());
+  entries->push_back(std::make_pair(origin.spec(), budget));
+  std::unique_ptr<std::vector<std::string>> keys_to_remove(
+      new std::vector<std::string>());
+  db_->UpdateEntries(std::move(entries), std::move(keys_to_remove), callback);

[Peter Beverloo, 2016/06/30 13:12:46]

micro nit: blank lines to separate the logical sections in this method could
reduce the "blob of code" feeling.

[harkness, 2016/07/01 12:29:54]

Good point.

+}