transcoding: add SimulatedTranscoder to test service

- Add SimulatedTranscoder (which is an upgraded version of
  DummyTranscoder) to allow more testing of the service.

- Add unit test that launches dummy test apps from shell
  to simulate uid policy change.

bug: 154734285
bug: 145233472
test: unit tests

Change-Id: Ic169757d64ad8da7eebd0e1febdcbfb467fe81f4
diff --git a/services/mediatranscoding/tests/TranscodingUidPolicyTestApp/TestAppB.xml b/services/mediatranscoding/tests/TranscodingUidPolicyTestApp/TestAppB.xml
new file mode 100644
index 0000000..e1e7857
--- /dev/null
+++ b/services/mediatranscoding/tests/TranscodingUidPolicyTestApp/TestAppB.xml
@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2020 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.android.tests.transcoding.testapp.B"
+    android:versionCode="1"
+    android:versionName="1.0" >
+
+    <application android:label="TestAppB">
+        <activity android:name="com.android.tests.transcoding.MainActivity">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.DEFAULT"/>
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+</manifest>
+