Increase font weight in LetterTileDrawables

Bug: 16683381
Change-Id: I9b9181fa25400b5d801bb6490042a2dcc722c6a3
diff --git a/res-common/values/strings.xml b/res-common/values/strings.xml
index ce2abc9..d074717 100644
--- a/res-common/values/strings.xml
+++ b/res-common/values/strings.xml
@@ -746,7 +746,7 @@
 
     <!-- Font family used when drawing letters for letter tile avatars.
          Do not translate. -->
-    <string name="letter_tile_letter_font_family">sans-serif-thin</string>
+    <string name="letter_tile_letter_font_family">sans-serif-light</string>
 
     <!-- Content description for the fake action menu up button as used
      inside search. [CHAR LIMIT=NONE] -->