Notify keyboard language on space bar when it has changed

This change also introduces the following.
* space bar language switcher is enabled for phone device.
* get rid of spcae key icon from number keyboard of tablet.
* slightly lower the position of language name on space bar of tablet.

Bug: 3290290
Change-Id: I432be8f757bcc84c257770112ff1f6fa7970c584
diff --git a/java/res/values-xlarge/config.xml b/java/res/values-xlarge/config.xml
index 56b9a16..410b5e1 100644
--- a/java/res/values-xlarge/config.xml
+++ b/java/res/values-xlarge/config.xml
@@ -28,6 +28,9 @@
     <bool name="config_digit_popup_characters_enabled">false</bool>
     <!-- Whether or not Popup on key press is enabled by default -->
     <bool name="config_default_popup_preview">false</bool>
+    <bool name="config_use_spacebar_language_switcher">false</bool>
+    <!-- The language is never displayed if == 0, always displayed if < 0 -->
+    <integer name="config_delay_before_fadeout_language_on_spacebar">1200</integer>
     <!-- This configuration is the index of the array {@link KeyboardSwitcher.KEYBOARD_THEMES}. -->
     <string name="config_default_keyboard_theme_id" translatable="false">5</string>
     <string name="config_text_size_of_language_on_spacebar" translatable="false">medium</string>