Switching to system user before CtsMidiTestCases module.

MidiService only works for user 0. Using a target provider, we
switch to user 0 before the module execution, and switch back
to whatever user we were in after we're done.

Change-Id: I3e326798bc498735300b697435c2edccb009d4a0
Fixes: 115906554
Test: While being in a secondary user, run: cts-tradefed run cts-dev -m CtsMidiTestCases
diff --git a/tests/tests/midi/AndroidTest.xml b/tests/tests/midi/AndroidTest.xml
index d8d12e2..23c305e 100644
--- a/tests/tests/midi/AndroidTest.xml
+++ b/tests/tests/midi/AndroidTest.xml
@@ -16,6 +16,9 @@
 <configuration description="Config for CTS MIDI test cases">
     <option name="test-suite-tag" value="cts" />
     <option name="config-descriptor:metadata" key="component" value="media" />
+    <target_preparer class="com.android.tradefed.targetprep.SwitchUserTargetPreparer">
+        <option name="user-type" value="system" />
+    </target_preparer>
     <target_preparer class="com.android.tradefed.targetprep.suite.SuiteApkInstaller">
         <option name="cleanup-apks" value="true" />
         <option name="test-file-name" value="CtsMidiTestCases.apk" />