Test to ensure a toast doesn't affect app standby

Put an app in standby, make it show a toast and ensure
that it doesn't come out of standby. This is to test
for a bug fix for the same behavior.

Bug: 31544592
Test: cts-tradefed run commandAndExit cts -m CtsHostsideNetworkTests -t com.android.cts.net.HostsideRestrictBackgroundNetworkTests#testAppIdle_toast
Change-Id: I796ecde8e346c308a27969d873e3ce384414fee3
diff --git a/tests/cts/hostside/app2/AndroidManifest.xml b/tests/cts/hostside/app2/AndroidManifest.xml
index 1fa49ba..adf0045 100644
--- a/tests/cts/hostside/app2/AndroidManifest.xml
+++ b/tests/cts/hostside/app2/AndroidManifest.xml
@@ -46,6 +46,7 @@
                 <action android:name="com.android.cts.net.hostside.app2.action.GET_RESTRICT_BACKGROUND_STATUS" />
                 <action android:name="com.android.cts.net.hostside.app2.action.CHECK_NETWORK" />
                 <action android:name="com.android.cts.net.hostside.app2.action.SEND_NOTIFICATION" />
+                <action android:name="com.android.cts.net.hostside.app2.action.SHOW_TOAST" />
                 </intent-filter>
         </receiver>
     </application>