Add warning on enabling ANGLE.

Enabling ANGLE on incompatible devices may cause some applications to
crash, add a warning.

Bug: b/287909344
Test: atest SettingsRoboTests:GraphicsDriverEnableAngleAsSystemDriverControllerTest
Change-Id: I4f856ee1912a59052a6aaf7dff087ce1b649935e
diff --git a/res/values/strings.xml b/res/values/strings.xml
index e254974..4267250 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -10530,7 +10530,7 @@
     <!-- Debugging developer settings: enable angle as system driver? [CHAR LIMIT=50] -->
     <string name="enable_angle_as_system_driver">Enable ANGLE</string>
     <!-- Debugging developer settings: enable angle as system driver summary [CHAR LIMIT=NONE] -->
-    <string name="enable_angle_as_system_driver_summary">Enable ANGLE as system OpenGL ES driver</string>
+    <string name="enable_angle_as_system_driver_summary">Enable ANGLE as default OpenGL ES driver. Enabling it on incompatible devices may break some applications.</string>
     <!--Dialog body text used to explain a reboot is required after changing ANGLE as system GLES driver setting-->
     <string name="reboot_dialog_enable_angle_as_system_driver">A reboot is required to change the system OpenGL ES driver</string>