Add keyLabelAlign attribute to Keyboard XML

Bug: 3216592
Change-Id: I88f8055199f2cd0525faf9374114fbebba53b951
diff --git a/java/res/values/strings.xml b/java/res/values/strings.xml
index cc513ae..018a1f9 100644
--- a/java/res/values/strings.xml
+++ b/java/res/values/strings.xml
@@ -226,6 +226,12 @@
     <string name="label_alpha_key">ABC</string>
     <!-- Label for ALT modifier key.  Must be short to fit on key! -->
     <string name="label_alt_key">ALT</string>
+    <!-- Label for Backspace modifier key.  Must be short to fit on key! -->
+    <string name="label_backspace_key">Backspace</string>
+    <!-- Label for Shift modifier key.  Must be short to fit on key! -->
+    <string name="label_shift_key">Shift</string>
+    <!-- Label for Return key.  Must be short to fit on key! -->
+    <string name="label_return_key">Return</string>
     <!-- Label for Shift modifier key of symbol keyboard.  Must be short to fit on key! -->
     <string name="label_more_key">More</string>
     <!-- Label for "Tab" key.  Must be short to fit on key! [CHAR LIMIT=4]-->