BControllable: Fix real_time and perf_time mismatch

* It caused parameters to change with delay, because the
event has been enqueued in the event queue with real time.
* Please don't rely on system_time.
* Fixes #5106.

src/kits/media/Controllable.cpp

@@ -39,6 +39,7 @@
 #include <OS.h>
 #include <ParameterWeb.h>
 #include <Roster.h>
+#include <TimeSource.h>
 
 #include <debug.h>
 #include <DataExchange.h>
@@ -233,7 +234,16 @@ BControllable::HandleMessage(int32 message, const void* data, size_t size)
 				return B_OK;
 			}
 
-			SetParameterValue(request.parameter_id, request.when,
+			// NOTE: This is not very fair, but the alternative
+			// would have been to mess with friends classes and
+			// member variables.
+			bigtime_t perfTime = 0;
+			if (request.when == -1)
+				perfTime = TimeSource()->Now();
+			else
+				perfTime = request.when;
+
+			SetParameterValue(request.parameter_id, perfTime,
 				transfer.Data(), request.size);
 			request.SendReply(B_OK, &reply, sizeof(reply));
 			return B_OK;

src/kits/media/DefaultMediaTheme.cpp

@@ -650,7 +650,7 @@ ContinuousMessageFilter::Filter(BMessage *message, BHandler **target)
 			"channels\n", fControl->Name(), fParameter.CountChannels());
 
 		if (fParameter.SetValue((void *)value, sizeof(value),
-				system_time()) < B_OK) {
+				-1) < B_OK) {
 			ERROR("ContinuousMessageFilter::Filter: Could not set parameter "
 				"value for %p\n", &fParameter);
 			return B_DISPATCH_MESSAGE;
@@ -760,7 +760,7 @@ DiscreteMessageFilter::Filter(BMessage *message, BHandler **target)
 
 	TRACE("DiscreteMessageFilter::Filter: update view %s, value = %ld\n", control->Name(), value);
 
-	if (fParameter.SetValue((void *)&value, sizeof(value), system_time()) < B_OK) {
+	if (fParameter.SetValue((void *)&value, sizeof(value), -1) < B_OK) {
 		ERROR("DiscreteMessageFilter::Filter: Could not set parameter value for %p\n", &fParameter);
 		return B_DISPATCH_MESSAGE;
 	}