Support partitioning of storage contexts based on render_id.

content/browser/storage_partition_map.h

+// Copyright (c) 2012 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_BROWSER_STORAGE_PARTITION_MAP_H_
+#define CONTENT_BROWSER_STORAGE_PARTITION_MAP_H_
+
+#include <map>
+#include <string>
+
+#include "base/callback_forward.h"
+#include "base/supports_user_data.h"
+
+namespace content {
+class BrowserContext;
+}
+
+class FilePath;
+class StoragePartition;
+
+// A std::string to StoragePartition map for use with SupportsUserData APIs.
+class StoragePartitionMap : public base::SupportsUserData::Data {

[jam, 2012/07/11 23:36:31]

ditto

[awong, 2012/07/12 20:28:40]

Done.

+ public:
+  explicit StoragePartitionMap(content::BrowserContext* browser_context);
+
+  virtual ~StoragePartitionMap();
+
+  // This map retains ownership of the returned StoragePartition objects.
+  StoragePartition* Get(const std::string& partition_id);
+
+  void ForEach(const base::Callback<void(StoragePartition*)>& callback);
+
+ private:
+  // TODO(ajwong): This must always be called *after* it's been added to the
+  // partition map.  This feels dangerous.  Should this not be in this class?

[jam, 2012/07/11 23:36:31]

i'm not sure i understand this comment. I would find it dangerous if it has to
be called, but the embedder is the one responsible. since you control this
class, why is it dangerous?

[awong, 2012/07/12 20:28:40]

It's not dangerous for users of the class, but for future maintainers.  When I
was refactoring this, I kept having code paths where this wasn't called at the
right time which took me time to track down.

I think we can actually remove the need for this function, so this comment is to
remind myself about the issue when I get to seeing how to make AppCache and
ResourceContext reflect the storage isolation.

Reworded it slightly to be more clear.

+  void PostCreateInitialization(StoragePartition* partition,
+                                const FilePath& partition_path);
+
+  content::BrowserContext* browser_context_;  // Not Owned.
+  std::map<std::string, StoragePartition*> partitions_;
+};
+
+#endif  // CONTENT_BROWSER_STORAGE_PARTITION_MAP_H_