Fix issues related to request and context object lifespan (issue #1037, issue #1044).

- Simplify and document the relationship between the various context object types. See browser_context.h for a description of the new relationships.
- cefclient: Add `request-context-per-browser` command-line flag for testing multiple CefRequestContext instances.
- cefclient: Add a CefURLRequest example.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@2032 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef/browser/resource_context.h

@@ -0,0 +1,39 @@
+// Copyright (c) 2015 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 CEF_LIBCEF_BROWSER_RESOURCE_CONTEXT_H_
+#define CEF_LIBCEF_BROWSER_RESOURCE_CONTEXT_H_
+#pragma once
+
+#include "content/public/browser/resource_context.h"
+
+class CefURLRequestContextGetter;
+
+// Acts as a bridge for resource loading. Life span is controlled by
+// CefBrowserContext. Created on the UI thread but accessed and destroyed on the
+// IO thread. URLRequest objects are associated with the ResourceContext via
+// ResourceDispatcherHost. When the ResourceContext is destroyed all outstanding
+// URLRequest objects will be deleted via the ResourceLoader that owns them and
+// removed from the associated URLRequestContext. Other URLRequest objects may
+// be created via URLFetcher that are not associated with a RequestContext.
+// See browser_context.h for an object relationship diagram.
+class CefResourceContext : public content::ResourceContext {
+ public:
+  CefResourceContext();
+  ~CefResourceContext() override;
+
+  // ResourceContext implementation.
+  net::HostResolver* GetHostResolver() override;
+  net::URLRequestContext* GetRequestContext() override;
+
+  void set_url_request_context_getter(
+      scoped_refptr<CefURLRequestContextGetter> getter);
+
+ private:
+  scoped_refptr<CefURLRequestContextGetter> getter_;
+
+  DISALLOW_COPY_AND_ASSIGN(CefResourceContext);
+};
+
+#endif  // CEF_LIBCEF_BROWSER_RESOURCE_CONTEXT_H_