Revert keyHintLetterPadding only to apply horizontally

Partially reverts the Ia3680d84.

Bug: 6356125
Change-Id: I8faa810b833cb98ce6f0f760aa1722e63475cd45
diff --git a/java/res/values/attrs.xml b/java/res/values/attrs.xml
index c78013f..e14633a 100644
--- a/java/res/values/attrs.xml
+++ b/java/res/values/attrs.xml
@@ -64,7 +64,7 @@
         <attr name="keyShiftedLetterHintRatio" format="float" />
         <!-- Horizontal padding of left/right aligned key label to the edge of the key. -->
         <attr name="keyLabelHorizontalPadding" format="dimension" />
-        <!-- Top and right padding of hint letter to the edge of the key.-->
+        <!-- Right padding of hint letter to the edge of the key.-->
         <attr name="keyHintLetterPadding" format="dimension" />
         <!-- Bottom padding of popup hint letter "..." to the edge of the key.-->
         <attr name="keyPopupHintLetterPadding" format="dimension" />