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/layout/suggestions_strip.xml b/java/res/layout/suggestions_strip.xml
index 0b61499..bff9a1e 100644
--- a/java/res/layout/suggestions_strip.xml
+++ b/java/res/layout/suggestions_strip.xml
@@ -24,12 +24,16 @@
         android:id="@+id/suggestions_strip"
         android:orientation="horizontal"
         android:layout_width="match_parent"
-        android:layout_height="match_parent" />
+        android:layout_height="match_parent"
+        android:layout_marginLeft="@dimen/config_suggestions_strip_horizontal_margin"
+        android:layout_marginRight="@dimen/config_suggestions_strip_horizontal_margin" />
     <LinearLayout
         android:id="@+id/add_to_dictionary_strip"
         android:orientation="horizontal"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
+        android:layout_marginLeft="@dimen/config_suggestions_strip_horizontal_margin"
+        android:layout_marginRight="@dimen/config_suggestions_strip_horizontal_margin"
         android:visibility="invisible">
         <TextView
             android:id="@+id/word_to_save"
@@ -49,7 +53,9 @@
         android:id="@+id/important_notice_strip"
         android:orientation="horizontal"
         android:layout_width="match_parent"
-        android:layout_height="match_parent">
+        android:layout_height="match_parent"
+        android:layout_marginLeft="@dimen/config_suggestions_strip_horizontal_margin"
+        android:layout_marginRight="@dimen/config_suggestions_strip_horizontal_margin">
         <TextView
             android:id="@+id/important_notice_title"
             android:layout_width="match_parent"