AudioParameter: Document usage of exiting and closing.

Ensure only privileged access.
Log warning message on setParameters failure
to prevent entering standby silently.

Test: adb shell dumpsys media.audio_flinger
Bug: 73175392
Bug: 270480994
Bug: 279106598
Merged-In: Ie38ee93e98ff2164f9076b8b6b7831cc6b7a8896
Change-Id: Ie38ee93e98ff2164f9076b8b6b7831cc6b7a8896
diff --git a/media/libaudiohal/impl/StreamHalAidl.cpp b/media/libaudiohal/impl/StreamHalAidl.cpp
index 6c43591..eccdfe8 100644
--- a/media/libaudiohal/impl/StreamHalAidl.cpp
+++ b/media/libaudiohal/impl/StreamHalAidl.cpp
@@ -436,8 +436,7 @@
     ALOGD("%p %s::%s", this, getClassName().c_str(), __func__);
     TIME_CHECK();
     if (!mStream) return NO_INIT;
-    ALOGE("%s not implemented yet", __func__);
-    return OK;
+    return statusTFromBinderStatus(mStream->prepareToClose());
 }
 
 status_t StreamHalAidl::createMmapBuffer(int32_t minSizeFrames __unused,
diff --git a/media/libaudiohal/impl/StreamHalHidl.cpp b/media/libaudiohal/impl/StreamHalHidl.cpp
index 192790c..2b0af49 100644
--- a/media/libaudiohal/impl/StreamHalHidl.cpp
+++ b/media/libaudiohal/impl/StreamHalHidl.cpp
@@ -979,9 +979,10 @@
 }
 
 status_t StreamOutHalHidl::exit() {
-    // FIXME this is using hard-coded strings but in the future, this functionality will be
-    //       converted to use audio HAL extensions required to support tunneling
-    return setParameters(String8("exiting=1"));
+    // Signal exiting to remote_submix HAL.
+    AudioParameter param;
+    param.addInt(String8(AudioParameter::keyExiting), 1);
+    return setParameters(param.toString());
 }
 
 StreamInHalHidl::StreamInHalHidl(