Switch LevelDBWrapper::GetAll to use the new Mojo sync IPC mechanism.

content/renderer/dom_storage/local_storage_cached_area.h

+// 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.
+
+#ifndef CONTENT_RENDERER_DOM_STORAGE_LOCAL_STORAGE_CACHED_AREA_H_
+#define CONTENT_RENDERER_DOM_STORAGE_LOCAL_STORAGE_CACHED_AREA_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/strings/nullable_string16.h"
+#include "content/common/leveldb_wrapper.mojom.h"
+#include "mojo/public/cpp/bindings/binding.h"
+#include "url/gurl.h"
+#include "url/origin.h"
+
+namespace content {
+class LocalStorageCachedAreas;
+class StoragePartitionService;
+
+// An in-process implementation of LocalStorage using a LevelDB Mojo service.
+// Maintains a complete cache of the origin's Map of key/value pairs for fast
+// access. The cache is primed on first access and changes are written to the
+// backend through the level db interface pointer. Mutations originating in
+// other processes are applied to the cache via LevelDBObserver callbacks.
+class LocalStorageCachedArea : public LevelDBObserver,
+                               public base::RefCounted<LocalStorageCachedArea> {
+ public:
+  LocalStorageCachedArea(const url::Origin& origin,
+                         StoragePartitionService* storage_partition_service,
+                         LocalStorageCachedAreas* cached_areas);
+
+  // These correspond to blink::WebStorageArea.
+  unsigned GetLength();
+  base::NullableString16 GetKey(unsigned index);
+  base::NullableString16 GetItem(const base::string16& key);
+  bool SetItem(const base::string16& key,
+               const base::string16& value,
+               const GURL& page_url);
+  void RemoveItem(const base::string16& key,
+                  const GURL& page_url);
+  void Clear(const GURL& page_url);
+
+  const url::Origin& origin() { return origin_; }
+
+ private:
+  friend class base::RefCounted<LocalStorageCachedArea>;
+  ~LocalStorageCachedArea() override;
+
+  // LevelDBObserver:
+  void KeyChanged(mojo::Array<uint8_t> key,
+                  mojo::Array<uint8_t> new_value,
+                  mojo::Array<uint8_t> old_value,
+                  const mojo::String& source) override;
+  void KeyDeleted(mojo::Array<uint8_t> key,
+                  const mojo::String& source) override;
+  void AllDeleted(const mojo::String& source) override;
+
+  // Synchronously fetches the origin's local storage data if it hasn't been
+  // fetched already.
+  void EnsureLoaded();
+
+  bool loaded_;
+  url::Origin origin_;
+  LevelDBWrapperPtr leveldb_;
+  mojo::Binding<LevelDBObserver> binding_;
+  LocalStorageCachedAreas* cached_areas_;
+
+  DISALLOW_COPY_AND_ASSIGN(LocalStorageCachedArea);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_DOM_STORAGE_LOCAL_STORAGE_CACHED_AREA_H_