Shortened the "Restrict background data" string so it won't trucate.
Bug: 5255012

Change-Id: Id8d403952330c56ffdb263ebf8cfce3036864678

Added char limit to string comment.
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 78b18c0..f8d0e9a 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -3455,8 +3455,8 @@
     <string name="data_usage_cycle">Data usage cycle</string>
     <!-- Title for checkbox menu option to enable mobile data when roaming. [CHAR LIMIT=32] -->
     <string name="data_usage_menu_roaming">Data roaming</string>
-    <!-- Title for checkbox menu option to restrict background data usage. [CHAR LIMIT=32] -->
-    <string name="data_usage_menu_restrict_background">Restrict background data</string>
+    <!-- Title for checkbox menu option to restrict background data usage. [CHAR LIMIT=20] -->
+    <string name="data_usage_menu_restrict_background">Restrict data</string>
     <!-- Title for checkbox menu option to show 4G mobile data usage separate from other mobile data usage. [CHAR LIMIT=32] -->
     <string name="data_usage_menu_split_4g">Separate 4G usage</string>
     <!-- Title for checkbox menu option to show Wi-Fi data usage. [CHAR LIMIT=32] -->