Check AID_RADIO correctly

AID_RADIO is just an appId. It has a different UID assigned
for each user on the device. When checking if the caller is
radio, extract the AID first and just check that.

This is a followup to some earlier targeted fixes to these
checks that partially/fully missed multiuser cases:

 - Ide5e9218811e110997fed19f43eb6a5fdc5812ec
 - I740b4f5acb88821197e3c4023a4032babd48ec5a
 - If5c721c9acfc78f1cbc35c3056adad95a4604f8b

This fixes a 10 second black screen caused by the dialer app
timing out while it waits, futilely, for media.metrics to become
visible to its process.

Repro as follows (must be on a secondary user):

 - adb shell am switch-user 10
 - adb shell pm clear com.android.phone
 - adb shell am start -n com.android.phone/.EmergencyDialer

Flag: EXEMPT trivial bugfix
Fix: 352390759
Test: Manual invocation of emergency dialer per above instructions
Change-Id: I2c8a6cc0459a6b46f482797e1456e30a70a43622
diff --git a/media/libmediametrics/MediaMetricsItem.cpp b/media/libmediametrics/MediaMetricsItem.cpp
index ecb248d..2c58461 100644
--- a/media/libmediametrics/MediaMetricsItem.cpp
+++ b/media/libmediametrics/MediaMetricsItem.cpp
@@ -334,21 +334,21 @@
 
     // This is checked only once in the lifetime of the process.
     const uid_t uid = getuid();
-    switch (uid) {
-    case AID_RADIO:     // telephony subsystem, RIL
+    const uid_t appid = multiuser_get_app_id(uid);
+
+    if (appid == AID_RADIO) {
+        // telephony subsystem, RIL
         return false;
-    default:
+    }
+
+    if (appid >= AID_ISOLATED_START && appid <= AID_ISOLATED_END) {
         // Some isolated processes can access the audio system; see
         // AudioSystem::setAudioFlingerBinder (currently only the HotwordDetectionService). Instead
         // of also allowing access to the MediaMetrics service, it's simpler to just disable it for
         // now.
         // TODO(b/190151205): Either allow the HotwordDetectionService to access MediaMetrics or
         // make this disabling specific to that process.
-        uid_t appid = multiuser_get_app_id(uid);
-        if (appid >= AID_ISOLATED_START && appid <= AID_ISOLATED_END) {
-            return false;
-        }
-        break;
+        return false;
     }
 
     int enabled = property_get_int32(Item::EnabledProperty, -1);