Fix PPB_MouseLock.LockMouse crash and add tests.

ppapi/proxy/ppb_instance_proxy.cc

 // 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.
 
 #include "ppapi/proxy/ppb_instance_proxy.h"
 
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/c/pp_time.h"
 #include "ppapi/c/pp_var.h"
 #include "ppapi/c/ppb_audio_config.h"
@@ skipping 627 matching lines @@
   EnterInstanceNoLock enter(instance);
   if (enter.succeeded())
     enter.functions()->PostMessage(instance, message.Get(dispatcher()));
 }
 
 void PPB_Instance_Proxy::OnHostMsgLockMouse(PP_Instance instance) {
   // Need to be careful to always issue the callback.
   pp::CompletionCallback cb = callback_factory_.NewCallback(
       &PPB_Instance_Proxy::MouseLockCompleteInHost, instance);
 
-  EnterInstanceNoLock enter(instance);
-  if (enter.failed()) {
-    cb.Run(PP_ERROR_BADARGUMENT);
-    return;
-  }
-  int32_t result = enter.functions()->LockMouse(instance,
-                                                enter.callback());
-  if (result != PP_OK_COMPLETIONPENDING)
-    cb.Run(result);
+  EnterInstanceNoLock enter(instance, cb.pp_completion_callback());
+  if (enter.succeeded())
+    enter.SetResult(enter.functions()->LockMouse(instance, enter.callback()));
 }
 
 void PPB_Instance_Proxy::OnHostMsgUnlockMouse(PP_Instance instance) {
   EnterInstanceNoLock enter(instance);
   if (enter.succeeded())
     enter.functions()->UnlockMouse(instance);
 }
 
 void PPB_Instance_Proxy::OnHostMsgGetDefaultPrintSettings(
     PP_Instance instance,
@@ skipping 118 matching lines @@
   }
 }
 
 void PPB_Instance_Proxy::OnPluginMsgMouseLockComplete(PP_Instance instance,
                                                       int32_t result) {
   // Save the mouse callback on the instance data.
   InstanceData* data = static_cast<PluginDispatcher*>(dispatcher())->
       GetInstanceData(instance);
   if (!data)
     return;  // Instance was probably deleted.
-  if (TrackedCallback::IsPending(data->mouse_lock_callback)) {
+  if (!TrackedCallback::IsPending(data->mouse_lock_callback)) {
     NOTREACHED();
     return;
   }
   TrackedCallback::ClearAndRun(&(data->mouse_lock_callback), result);
 }
 
 void PPB_Instance_Proxy::MouseLockCompleteInHost(int32_t result,
                                                  PP_Instance instance) {
   dispatcher()->Send(new PpapiMsg_PPBInstance_MouseLockComplete(
       API_ID_PPB_INSTANCE, instance, result));
 }
 
 }  // namespace proxy
 }  // namespace ppapi