Added toast message to color temperature setting

Added a toast message to inform the user that the color temperature
setting is applied once the display is off.

Bug:26110238
Change-Id: Ia773581eb441ed2f4ac44b20e611ad3700e8abbf

src/com/android/settings/DevelopmentSettings.java

@@ -71,6 +71,7 @@ import android.view.ViewGroup;
 import android.view.accessibility.AccessibilityManager;
 import android.widget.Switch;
 import android.widget.TextView;
+import android.widget.Toast;
 
 import com.android.internal.logging.MetricsLogger;
 import com.android.settings.fuelgauge.InactiveApps;
@@ -1197,6 +1198,7 @@ public class DevelopmentSettings extends SettingsPreferenceFragment
         SystemProperties.set(COLOR_TEMPERATURE_PROPERTY,
                 mColorTemperaturePreference.isChecked() ? "1" : "0");
         pokeSystemProperties();
+        Toast.makeText(getActivity(), R.string.color_temperature_toast, Toast.LENGTH_LONG).show();
     }
 
     private void updateUSBAudioOptions() {