Use battery unplugging event to compute the full charge start time on

Pixel devices.

Test: make RunSettingsRoboTests + manual
Bug: 256124406
Change-Id: I80b33db6e25ac0c693c50ddf93b6343c0fea942f

src/com/android/settings/fuelgauge/PowerUsageFeatureProvider.java

@@ -133,10 +133,15 @@ public interface PowerUsageFeatureProvider {
     boolean delayHourlyJobWhenBooting();
 
     /**
-     * Gets a intent for one time bypass charge limited to resume charging.
+     * Gets an intent for one time bypass charge limited to resume charging.
      */
     Intent getResumeChargeIntent(boolean isDockDefender);
 
+    /**
+     * Returns the intent action used to mark as the full charge start event.
+     */
+    String getFullChargeIntentAction();
+
     /**
      * Returns {@link Set} for the system component ids which are combined into others
      */