[2/2] OmniGears: add config to apply custom shadow on header images

To make text and status icons better visible with bright
images if required.

Change-Id: Idafa96bf1e07c91ef6e3e62efbe6aa505d9d9892
diff --git a/res/values/custom_strings.xml b/res/values/custom_strings.xml
index e7fe400..6e9a6c1 100644
--- a/res/values/custom_strings.xml
+++ b/res/values/custom_strings.xml
@@ -217,6 +217,9 @@
     <string name="status_bar_custom_header_title">Custom header image</string>
     <string name="status_bar_custom_header_summary">Enable notification panel header image</string>
     <string name="daylight_header_pack_title">Header image pack</string>
+    <string name="status_bar_custom_header_shadow_title">Header image shadow</string>
+    <string name="status_bar_custom_header_shadow_summary">For better visibility on bright images</string>
+    <string name="unit_percent">\u0025</string>
 
     <!-- Network traffic -->
     <string name="network_traffic_title">Network traffic</string>