Make RotaryService use demo RotaryIME on emulator

Overlay rotary_input_method on emulator to refer to the demo rotary IME.

Test: manual
Bug: 165030003
Change-Id: I28e91efe3cba50a59f70df1daf25c693aa1afb52
diff --git a/emulator/rotary/car_rotary.mk b/emulator/rotary/car_rotary.mk
index 8efcfe5..0ac9c73 100644
--- a/emulator/rotary/car_rotary.mk
+++ b/emulator/rotary/car_rotary.mk
@@ -17,3 +17,5 @@
 
 PRODUCT_PACKAGES += CarRotaryController
 PRODUCT_PACKAGES += RotaryIME
+
+DEVICE_PACKAGE_OVERLAYS += device/generic/car/emulator/rotary/overlay
diff --git a/emulator/rotary/overlay/packages/apps/Car/RotaryController/res/values/strings.xml b/emulator/rotary/overlay/packages/apps/Car/RotaryController/res/values/strings.xml
new file mode 100644
index 0000000..751c980
--- /dev/null
+++ b/emulator/rotary/overlay/packages/apps/Car/RotaryController/res/values/strings.xml
@@ -0,0 +1,20 @@
+<?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.
+  -->
+<resources>
+    <!-- Component name of rotary IME. Empty if none. Overlaid to use demo rotary IME. -->
+    <string name="rotary_input_method" translatable="false">com.android.car.rotaryime/.RotaryIme</string>
+</resources>