Send BATTERY_CHANGED if maxChargingCurrent changes

Fixes a bug where the charging current on Keyguard was stale
on devices that don't immediately set the charging current.

Follow-up to I2e5c21dd7ec028ce47fb03ab71e74f7fccaa9e36

Bug: 8099739
Change-Id: I4b5b3b1231b1372310206941386dba743d5f88f4
diff --git a/services/core/java/com/android/server/BatteryService.java b/services/core/java/com/android/server/BatteryService.java
index 5160ddf..2eeaec9 100644
--- a/services/core/java/com/android/server/BatteryService.java
+++ b/services/core/java/com/android/server/BatteryService.java
@@ -120,6 +120,7 @@
     private int mLastBatteryVoltage;
     private int mLastBatteryTemperature;
     private boolean mLastBatteryLevelCritical;
+    private int mLastMaxChargingCurrent;
 
     private int mInvalidCharger;
     private int mLastInvalidCharger;
@@ -354,6 +355,7 @@
                 mPlugType != mLastPlugType ||
                 mBatteryProps.batteryVoltage != mLastBatteryVoltage ||
                 mBatteryProps.batteryTemperature != mLastBatteryTemperature ||
+                mBatteryProps.maxChargingCurrent != mLastMaxChargingCurrent ||
                 mInvalidCharger != mLastInvalidCharger)) {
 
             if (mPlugType != mLastPlugType) {
@@ -480,6 +482,7 @@
             mLastPlugType = mPlugType;
             mLastBatteryVoltage = mBatteryProps.batteryVoltage;
             mLastBatteryTemperature = mBatteryProps.batteryTemperature;
+            mLastMaxChargingCurrent = mBatteryProps.maxChargingCurrent;
             mLastBatteryLevelCritical = mBatteryLevelCritical;
             mLastInvalidCharger = mInvalidCharger;
         }