CMParts: Long-press power while display is off for torch

Add the switch for the following gesture:

  Long-press the power button while the display is off
  to switch the torchlight on.
  Press the power button again to switch it off.

Serhij Kyryljan: Port to CMParts.

Change-Id: I657c5fee6944e4a1e087e0c9e10fd43e5c8ea7f5
diff --git a/res/xml/button_settings.xml b/res/xml/button_settings.xml
index 544dc00..ad28e0c 100644
--- a/res/xml/button_settings.xml
+++ b/res/xml/button_settings.xml
@@ -15,6 +15,7 @@
 -->
 
 <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:cm="http://schemas.android.com/apk/res/cyanogenmod.platform"
         android:key="button_settings"
         android:title="@string/button_pref_title">
 
@@ -91,6 +92,13 @@
             android:summary="@string/power_end_call_summary"
             android:persistent="false"/>
 
+        <cyanogenmod.preference.CMSystemSettingSwitchPreference
+            android:key="torch_long_press_power_gesture"
+            android:title="@string/torch_long_press_power_gesture_title"
+            android:summary="@string/torch_long_press_power_gesture_desc"
+            android:defaultValue="false"
+            cm:requiresConfig="@*android:bool/config_supportLongPressPowerWhenNonInteractive" />
+
     </PreferenceCategory>
 
     <PreferenceCategory