Convert resources to take an instance key instead of an Instance*.

ppapi/cpp/url_loader.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 PPAPI_CPP_URL_LOADER_H_
 #define PPAPI_CPP_URL_LOADER_H_
 
 #include "ppapi/c/pp_stdint.h"
 #include "ppapi/cpp/resource.h"
 
 /// @file
 /// This file defines the API for loading URLs.
 namespace pp {
 
 class CompletionCallback;
-class Instance;
+class InstanceHandle;
 class URLRequestInfo;
 class URLResponseInfo;
 
 /// URLLoader provides an API for loading URLs.
 /// Refer to <code>ppapi/examples/url_loader/streaming.cc</code>
 /// for an example of how to use this class.
 class URLLoader : public Resource {
  public:
   /// Default constructor for creating an is_null()
   /// <code>URLLoader</code> object.
   URLLoader() {}
 
   // TODO(brettw) remove this when NaCl is updated to use the new version
   // that takes a pointer.
-  explicit URLLoader(const Instance& instance);
+  //explicit URLLoader(const Instance& instance);
 
   /// A constructor used when a <code>PP_Resource</code> is provided as a
   /// return value whose reference count we need to increment.
   ///
   /// @param[in] resource A <code>PP_Resource</code> corresponding to a
   /// <code>URLLoader</code> resource.
   explicit URLLoader(PP_Resource resource);
 
   /// A constructor used to allocate a new URLLoader in the browser. The
   /// resulting object will be <code>is_null</code> if the allocation failed.
   ///
-  /// @param[in] instance An <code>Instance</code>.
-  explicit URLLoader(Instance* instance);
+  /// @param[in] instance The instance with which this resource will be
+  /// associated.
+  explicit URLLoader(const InstanceHandle& instance);
 
   /// The copy constructor for <code>URLLoader</code>.
   ///
   /// @param other A <code>URLLoader</code> to be copied.
   URLLoader(const URLLoader& other);
 
   /// This function begins loading the <code>URLRequestInfo</code>.
   /// The operation completes when response headers are received or when an
   /// error occurs.  Use GetResponseInfo() to access the response
   /// headers.
@@ skipping 107 matching lines @@
   ///
   /// <strong>Note:</strong> If the <code>URLLoader</code> object is destroyed
   /// while it is still open, then it will be implicitly closed so you are not
   /// required to call Close().
   void Close();
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_URL_LOADER_H_