Revert "Do not allow apps to set night mode"

This reverts commit 9f4132fa4d5be2436766a802e22991510fe0dd8f.

Reason for revert: This change will break Android Auto and other users of night mode. There is an ongoing discussion to figure out path forward (See http://go/dt-aa-nm)

Change-Id: I37c97e62a3414be7a51a47614f312b97d647dea8
(cherry picked from commit 6e2d1880fc13a75b6405b94485a2ef8ca5f09219)
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 293d90e..c4f68e3 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -913,7 +913,7 @@
     <!--  Control whether to lock day/night mode change from normal application. When it is
           true, day / night mode change is only allowed to apps with MODIFY_DAY_NIGHT_MODE
           permission. -->
-    <bool name="config_lockDayNightMode">true</bool>
+    <bool name="config_lockDayNightMode">false</bool>
     <!-- Control the default night mode to use when there is no other mode override set.
          One of the following values (see