Use margin instead of padding in SuggestionStripView

This CL also tunes the width of suggestions strip to be able to
display 15~16 letters without x-scaling at the center slot.

Bug: 14419121
Change-Id: Ia5766cee043899533e24e2ebc621e8dc279370b3
diff --git a/java/res/values/config.xml b/java/res/values/config.xml
index 45ea483..1ab4927 100644
--- a/java/res/values/config.xml
+++ b/java/res/values/config.xml
@@ -64,10 +64,10 @@
     <fraction name="config_key_shifted_letter_hint_ratio_5row">41%</fraction>
 
     <dimen name="config_suggestions_strip_height">40dp</dimen>
+    <dimen name="config_suggestions_strip_horizontal_margin">0dp</dimen>
     <dimen name="config_more_suggestions_row_height">40dp</dimen>
     <integer name="config_max_more_suggestions_row">6</integer>
     <fraction name="config_min_more_suggestions_width">90%</fraction>
-    <dimen name="config_suggestions_strip_horizontal_padding">0dp</dimen>
     <dimen name="config_suggestion_min_width">44dp</dimen>
     <dimen name="config_suggestion_text_horizontal_padding">6dp</dimen>
     <dimen name="config_suggestion_text_size">18dp</dimen>