audio: filter reserved binder calls

Block incoming binder calls to audio flinger and audio policy service
for sensitive functions if they are not coming from a system UID.

Bug: 72278478
Test: audio smoke tests. CTS tests for AudioTrack and AudioRecord
Change-Id: I78e02efffe135d5450ced125e51e2084719ca03d
diff --git a/services/audiopolicy/service/AudioPolicyService.cpp b/services/audiopolicy/service/AudioPolicyService.cpp
index e5aed9a..90a5a0f 100644
--- a/services/audiopolicy/service/AudioPolicyService.cpp
+++ b/services/audiopolicy/service/AudioPolicyService.cpp
@@ -273,7 +273,7 @@
 void AudioPolicyService::NotificationClient::onDynamicPolicyMixStateUpdate(
         const String8& regId, int32_t state)
 {
-    if (mAudioPolicyServiceClient != 0) {
+    if (mAudioPolicyServiceClient != 0 && mUid < AID_APP_START) {
         mAudioPolicyServiceClient->onDynamicPolicyMixStateUpdate(regId, state);
     }
 }
@@ -283,7 +283,7 @@
         const audio_config_base_t *clientConfig, const audio_config_base_t *deviceConfig,
         audio_patch_handle_t patchHandle)
 {
-    if (mAudioPolicyServiceClient != 0) {
+    if (mAudioPolicyServiceClient != 0 && mUid < AID_APP_START) {
         mAudioPolicyServiceClient->onRecordingConfigurationUpdate(event, clientInfo,
                 clientConfig, deviceConfig, patchHandle);
     }