Use audio_session_t consistently

Bug: 27562099
Change-Id: I328d8226191386b163f2ace41233607294c50dcd
diff --git a/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp b/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp
index fdd6dd2..92a1285 100644
--- a/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp
+++ b/services/audiopolicy/service/AudioPolicyInterfaceImpl.cpp
@@ -476,7 +476,7 @@
 status_t AudioPolicyService::registerEffect(const effect_descriptor_t *desc,
                                 audio_io_handle_t io,
                                 uint32_t strategy,
-                                int session,
+                                audio_session_t session,
                                 int id)
 {
     if (mAudioPolicyManager == NULL) {
@@ -537,7 +537,7 @@
     return mAudioPolicyManager->isSourceActive(source);
 }
 
-status_t AudioPolicyService::queryDefaultPreProcessing(int audioSession,
+status_t AudioPolicyService::queryDefaultPreProcessing(audio_session_t audioSession,
                                                        effect_descriptor_t *descriptors,
                                                        uint32_t *count)
 {