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

ppapi/cpp/dev/message_loop_dev.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 PPAPI_CPP_DEV_MESSAGE_LOOP_DEV_H_
 #define PPAPI_CPP_DEV_MESSAGE_LOOP_DEV_H_
 
 #include "ppapi/cpp/resource.h"
 
 namespace pp {
 
 class CompletionCallback;
-class Instance;
+class InstanceHandle;
 
 /// A message loop allows PPAPI calls to be issued on a thread. You may not
 /// issue any API calls on a thread without creating a message loop. It also
 /// allows you to post work to the message loop for a thread.
 ///
 /// To process work posted to the message loop, as well as completion callbacks
 /// for asynchronous operations, you must run the message loop via Run().
 ///
 /// Note the system manages the lifetime of the instance (and all associated
 /// resources). If the instance is deleted from the page, background threads may
@@ skipping 104 matching lines @@
  public:
   /// Creates an is_null() MessageLoop resource.
   MessageLoop_Dev();
 
   /// Creates a message loop associated with the given instance. The resource
   /// will be is_null() on failure.
   ///
   /// This may be called from any thread. After your thread starts but before
   /// issuing any other PPAPI calls on it, you must associate it with a message
   /// loop by calling AttachToCurrentThread.
-  explicit MessageLoop_Dev(Instance* instance);
+  explicit MessageLoop_Dev(const InstanceHandle& instance);
 
   MessageLoop_Dev(const MessageLoop_Dev& other);
 
   /// Takes an additional ref to the resource.
   explicit MessageLoop_Dev(PP_Resource pp_message_loop);
 
   static MessageLoop_Dev GetForMainThread();
   static MessageLoop_Dev GetCurrent();
 
   /// Sets the given message loop resource as being the associated message loop
@@ skipping 103 matching lines @@
   ///   - PP_ERROR_BADRESOURCE: The message loop was invalid.
   ///   - PP_ERROR_WRONG_THREAD: You are attempting to quit the main thread.
   ///     The main thread's message loop is managed by the system and can't be
   ///     quit.
   int32_t PostQuit(bool should_destroy);
 };
 
 }  // namespace pp
 
 #endif  // PPAPI_CPP_DEV_MESSAGE_LOOP_DEV_H_