Add labels to intensity slider and flip labels

Labels are Dimmer and Brighter. As the slider value is lowered,
the dimming intensity is increased

Slider min = 100 - intensity max
Slider max = 100 - intensity min

Ex: If intensity max = 80, the slider min with be 20. If the user
moves the position to the minimum end we'll send 80 to Color DisplayManager

Test: atest ReduceBrightColorsIntensityPreferenceControllerTest,
manual
Bug: 190722076

Change-Id: Ib05ba38805b8fa1f68c144a3929027899df70abf

src/com/android/settings/accessibility/ReduceBrightColorsIntensityPreferenceController.java

@@ -28,6 +28,7 @@ import com.android.settings.widget.SeekBarPreference;
 /** PreferenceController for feature intensity. */
 public class ReduceBrightColorsIntensityPreferenceController extends SliderPreferenceController {
 
+    private static final int INVERSE_PERCENTAGE_BASE = 100;
     private final ColorDisplayManager mColorDisplayManager;
 
     public ReduceBrightColorsIntensityPreferenceController(Context context, String key) {
@@ -66,21 +67,24 @@ public class ReduceBrightColorsIntensityPreferenceController extends SliderPrefe
 
     @Override
     public int getSliderPosition() {
-        return mColorDisplayManager.getReduceBrightColorsStrength();
+        return INVERSE_PERCENTAGE_BASE - mColorDisplayManager.getReduceBrightColorsStrength();
     }
 
     @Override
     public boolean setSliderPosition(int position) {
-        return mColorDisplayManager.setReduceBrightColorsStrength(position);
+        return mColorDisplayManager.setReduceBrightColorsStrength(
+                INVERSE_PERCENTAGE_BASE - position);
     }
 
     @Override
     public int getMax() {
-        return ColorDisplayManager.getMaximumReduceBrightColorsStrength(mContext);
+        return INVERSE_PERCENTAGE_BASE
+                - ColorDisplayManager.getMinimumReduceBrightColorsStrength(mContext);
     }
 
     @Override
     public int getMin() {
-        return ColorDisplayManager.getMinimumReduceBrightColorsStrength(mContext);
+        return INVERSE_PERCENTAGE_BASE
+                - ColorDisplayManager.getMaximumReduceBrightColorsStrength(mContext);
     }
 }