BrightnessChangeEvent works for increasing brightness

BrightnessChangeEvents were only sending when decreasing the brightness.
Due to two issues:
1) brightness adjustment was being clamped to 0-1 instead of -1 to +1.
(meaning buggy conditions were met when 0.0 == 0.0)
2) the brightness reason that was being read was the old reason,
rather than the temporary (new) reason (meaning we were not sending
change events correctly).

Bug: 282005647
Test: adb shell dumpsys | grep BrightnessChangeEvent
Change-Id: I2ada97469b68baee695e06db0c8a0cdbbab1027f

services/core/java/com/android/server/display/DisplayPowerController2.java

@@ -1454,7 +1454,7 @@ final class DisplayPowerController2 implements AutomaticBrightnessController.Cal
         // Skip the animation when the screen is off or suspended.
         boolean brightnessAdjusted = false;
         final boolean brightnessIsTemporary =
-                (mBrightnessReason.getReason() == BrightnessReason.REASON_TEMPORARY)
+                (mBrightnessReasonTemp.getReason() == BrightnessReason.REASON_TEMPORARY)
                         || mAutomaticBrightnessStrategy
                         .isTemporaryAutoBrightnessAdjustmentApplied();
         if (!mPendingScreenOff) {
@@ -2159,11 +2159,6 @@ final class DisplayPowerController2 implements AutomaticBrightnessController.Cal
         }, mClock.uptimeMillis());
     }
 
-    private float getAutoBrightnessAdjustmentSetting() {
-        final float adj = Settings.System.getFloatForUser(mContext.getContentResolver(),
-                Settings.System.SCREEN_AUTO_BRIGHTNESS_ADJ, 0.0f, UserHandle.USER_CURRENT);
-        return Float.isNaN(adj) ? 0.0f : clampAutoBrightnessAdjustment(adj);
-    }
 
     @Override
     public float getScreenBrightnessSetting() {
@@ -2436,9 +2431,6 @@ final class DisplayPowerController2 implements AutomaticBrightnessController.Cal
         }
     }
 
-    private static float clampAutoBrightnessAdjustment(float value) {
-        return MathUtils.constrain(value, -1.0f, 1.0f);
-    }
 
     private void noteScreenState(int screenState) {
         // Log screen state change with display id

services/core/java/com/android/server/display/brightness/BrightnessUtils.java

@@ -41,6 +41,13 @@ public final class BrightnessUtils {
                 PowerManager.BRIGHTNESS_MAX);
     }
 
+    /**
+     * Clamps the brightness value in the maximum and the minimum brightness adjustment range
+     */
+    public static float clampBrightnessAdjustment(float value) {
+        return MathUtils.constrain(value, -1.0f, 1.0f);
+    }
+
     /**
      * A utility to construct the DisplayBrightnessState
      */

services/core/java/com/android/server/display/brightness/strategy/AutomaticBrightnessStrategy.java

@@ -202,7 +202,7 @@ public class AutomaticBrightnessStrategy {
         final float adj = Settings.System.getFloatForUser(mContext.getContentResolver(),
                 Settings.System.SCREEN_AUTO_BRIGHTNESS_ADJ, 0.0f, UserHandle.USER_CURRENT);
         mPendingAutoBrightnessAdjustment = Float.isNaN(adj) ? Float.NaN
-                : BrightnessUtils.clampAbsoluteBrightness(adj);
+                : BrightnessUtils.clampBrightnessAdjustment(adj);
         if (userSwitch) {
             processPendingAutoBrightnessAdjustments();
         }
@@ -402,6 +402,6 @@ public class AutomaticBrightnessStrategy {
     private float getAutoBrightnessAdjustmentSetting() {
         final float adj = Settings.System.getFloatForUser(mContext.getContentResolver(),
                 Settings.System.SCREEN_AUTO_BRIGHTNESS_ADJ, 0.0f, UserHandle.USER_CURRENT);
-        return Float.isNaN(adj) ? 0.0f : BrightnessUtils.clampAbsoluteBrightness(adj);
+        return Float.isNaN(adj) ? 0.0f : BrightnessUtils.clampBrightnessAdjustment(adj);
     }
 }