Clean up Settings and SettingsFragment a bit

Change-Id: I93bf3cb1ea7e8fc09f4ad34b0bdd74f5f5ff1a68
diff --git a/java/res/values-sw600dp/config.xml b/java/res/values-sw600dp/config.xml
index b47eacb..9527fd6 100644
--- a/java/res/values-sw600dp/config.xml
+++ b/java/res/values-sw600dp/config.xml
@@ -22,10 +22,10 @@
     <!-- Device form factor. This value must be aligned with {@link KeyboardId.FORM_FACTOR_TABLET7} -->
     <integer name="config_device_form_factor">1</integer>
     <bool name="config_enable_show_voice_key_option">false</bool>
-    <bool name="config_enable_show_popup_on_keypress_option">false</bool>
+    <bool name="config_enable_show_option_of_key_preview_popup">false</bool>
     <bool name="config_enable_bigram_suggestions_option">false</bool>
     <!-- Whether or not Popup on key press is enabled by default -->
-    <bool name="config_default_popup_preview">false</bool>
+    <bool name="config_default_key_preview_popup">false</bool>
     <bool name="config_default_sound_enabled">true</bool>
     <bool name="config_auto_correction_spacebar_led_enabled">false</bool>
     <!-- The language is never displayed if == 0, always displayed if < 0 -->
diff --git a/java/res/values-sw768dp/config.xml b/java/res/values-sw768dp/config.xml
index 5e79541..3c2c198 100644
--- a/java/res/values-sw768dp/config.xml
+++ b/java/res/values-sw768dp/config.xml
@@ -22,10 +22,10 @@
     <!-- Device form factor. This value must be aligned with {@link KeyboardId.FORM_FACTOR_TABLET10} -->
     <integer name="config_device_form_factor">2</integer>
     <bool name="config_enable_show_voice_key_option">false</bool>
-    <bool name="config_enable_show_popup_on_keypress_option">false</bool>
+    <bool name="config_enable_show_option_of_key_preview_popup">false</bool>
     <bool name="config_enable_bigram_suggestions_option">false</bool>
     <!-- Whether or not Popup on key press is enabled by default -->
-    <bool name="config_default_popup_preview">false</bool>
+    <bool name="config_default_key_preview_popup">false</bool>
     <bool name="config_default_sound_enabled">true</bool>
     <bool name="config_auto_correction_spacebar_led_enabled">false</bool>
     <!-- This configuration is the index of the array {@link KeyboardSwitcher.KEYBOARD_THEMES}. -->
diff --git a/java/res/values/config.xml b/java/res/values/config.xml
index 82166df..d248a68 100644
--- a/java/res/values/config.xml
+++ b/java/res/values/config.xml
@@ -23,11 +23,11 @@
     <integer name="config_device_form_factor">0</integer>
     <bool name="config_use_fullscreen_mode">false</bool>
     <bool name="config_enable_show_voice_key_option">true</bool>
-    <bool name="config_enable_show_popup_on_keypress_option">true</bool>
+    <bool name="config_enable_show_option_of_key_preview_popup">true</bool>
     <!-- TODO: Disable the following configuration for production. -->
     <bool name="config_enable_usability_study_mode_option">true</bool>
     <!-- Whether or not Popup on key press is enabled by default -->
-    <bool name="config_default_popup_preview">true</bool>
+    <bool name="config_default_key_preview_popup">true</bool>
     <!-- Default value for next word prediction: after entering a word and a space only, should we look
          at input history to suggest a hopefully helpful suggestions for the next word? -->
     <bool name="config_default_next_word_prediction">true</bool>
diff --git a/java/res/xml/prefs.xml b/java/res/xml/prefs.xml
index cff7505..da6e601 100644
--- a/java/res/xml/prefs.xml
+++ b/java/res/xml/prefs.xml
@@ -42,7 +42,7 @@
             android:key="popup_on"
             android:title="@string/popup_on_keypress"
             android:persistent="true"
-            android:defaultValue="@bool/config_default_popup_preview" />
+            android:defaultValue="@bool/config_default_key_preview_popup" />
         <ListPreference
             android:key="voice_mode"
             android:title="@string/voice_input"