Add popupKeyboardTemplate attribute to Keyboard

This change
- introduces the popupKeyboardTemplate attribute of Keyboard to
  specify XML Keyboard file for popup mini keyboard.
- introduces the maxPopupKeyboardColumn attribute of Keyboard to
  specify the maximum column of popup mini keyboard.
- changes the content format of the popupCharacters attribute of Key.
  It now represents keyLabel, codes and keyTextOutput of each key of
  popup mini keyboard using CSV format.

Bug: 2214959
Change-Id: I539e310f7e38a049ee193de0b4ad5d7afdce37b1
diff --git a/java/res/xml/kbd_qwerty.xml b/java/res/xml/kbd_qwerty.xml
index b102eb6..92d92f0 100644
--- a/java/res/xml/kbd_qwerty.xml
+++ b/java/res/xml/kbd_qwerty.xml
@@ -26,6 +26,8 @@
     latin:keyWidth="10%p"
     latin:horizontalGap="@dimen/key_horizontal_gap"
     latin:verticalGap="@dimen/key_bottom_gap"
+    latin:popupKeyboardTemplate="@xml/kbd_popup_template"
+    latin:maxPopupKeyboardColumn="@integer/config_max_popup_keyboard_column"
 >
     <include
         latin:keyboardLayout="@xml/kbd_qwerty_rows" />