Use a specific theme for the car user switching dialog.

Bug: 113502116
Test: Tested on device
Change-Id: I50ff82bd7ae0e39e5683fd2d97105d67ed62c128
(cherry picked from commit b08d7169a462c0c8741f05edbce5601670576a24)

core/res/res/values/symbols.xml

@@ -3515,6 +3515,7 @@
   <java-symbol type="layout" name="car_user_switching_dialog" />
   <java-symbol type="id" name="user_loading_avatar" />
   <java-symbol type="id" name="user_loading" />
+  <java-symbol type="style" name="Theme.DeviceDefault.Light.Dialog.Alert.UserSwitchingDialog" />
 
   <java-symbol type="string" name="battery_saver_description_with_learn_more" />
 

services/core/java/com/android/server/am/CarUserSwitchingDialog.java

@@ -65,7 +65,9 @@ final class CarUserSwitchingDialog extends UserSwitchingDialog {
         setCancelable(false);
         Resources res = getContext().getResources();
         // Custom view due to alignment and font size requirements
-        View view = LayoutInflater.from(getContext()).inflate(R.layout.car_user_switching_dialog,
+        getContext().setTheme(R.style.Theme_DeviceDefault_Light_Dialog_Alert_UserSwitchingDialog);
+        View view = LayoutInflater.from(getContext()).inflate(
+                R.layout.car_user_switching_dialog,
                 null);
 
         UserManager userManager =