Cleanup: Make quota dispatcher code independent from WebKit types

content/common/web_quota_dispatcher_callback.h

+// Copyright (c) 2011 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_COMMON_WEB_QUOTA_DISPATCHER_CALLBACK_H_
+#define CONTENT_COMMON_WEB_QUOTA_DISPATCHER_CALLBACK_H_
+
+#include "content/common/quota_dispatcher.h"
+
+namespace WebKit {
+class WebStorageQuotaCallbacks;
+}
+
+// QuotaDispatcherCallback implementation for WebStorageQuotaCallbacks.
+class WebQuotaDispatcherCallback : public QuotaDispatcher::Callback {

[michaeln, 2011/07/19 20:27:36]

This class name confused me a bit. I've come to expect classes starting with
"Web" are either defined in the WebKit API or derive from a such a class (maybe
not not always true, but generally that's the case).

Also, the layers of indirection when looking at how 'callbacks' work can obscure
what's going on, so i'd look for ways to avoid defining a new class at the
global scope.

If there aren't any other implementations of QuotaDispatcher::Callback on the
horizon? I wonder if code would be easier to follow if QuotaDispatcher::Callback
was a concrete impl instead of an abstract interface. Of course the
QuotaDispatcher would still have a dependency on the WebKit API in that case
which is part of what your trying to accomplish.

Another way to avoid introducing a new 'callback' class into the global
namespace  could be to define the concrete subclass that wraps the WebKit
callback class inside of an anon namespace within RenderView.cc... a hidden
helper class (QuotaCallbacksWrapper) instead of a top-level thing... less
cognitive weight feeling to me.

Wdyt?

At a minimum, please reconsider this class name so that it doesn't start with
"Web".

+ public:
+  WebQuotaDispatcherCallback(WebKit::WebStorageQuotaCallbacks* callbacks);
+  virtual ~WebQuotaDispatcherCallback();
+
+  virtual void DidQueryStorageUsageAndQuota(int64 usage, int64 quota) OVERRIDE;
+  virtual void DidGrantStorageQuota(int64 granted_quota) OVERRIDE;
+  virtual void DidFail(quota::QuotaStatusCode error) OVERRIDE;
+
+ private:
+  // Not owned (self-destructed).
+  WebKit::WebStorageQuotaCallbacks* callbacks_;
+};
+
+#endif  // CONTENT_COMMON_WEB_QUOTA_DISPATCHER_CALLBACK_H_