Add description of disabled voice input key option

Bug: 12377179
Change-Id: I44d35c6fa82883710674ecca6f630d09076472fe
diff --git a/java/res/values/strings.xml b/java/res/values/strings.xml
index f618473..8e8a13f 100644
--- a/java/res/values/strings.xml
+++ b/java/res/values/strings.xml
@@ -249,6 +249,8 @@
 
     <!-- Preferences item for enabling speech input -->
     <string name="voice_input">Voice input key</string>
+    <!-- The summary text to describe the reason why the "Voice input key" option is disabled. [CHAR LIMIT=100] -->
+    <string name="voice_input_disabled_summary">No voice input methods enabled. Check Language &amp; input settings.</string>
 
     <!-- Title for configuring input method settings [CHAR LIMIT=35] -->
     <string name="configure_input_method">Configure input methods</string>