Revert "Enforce declared permissions on getCellularBatteryStats() and getWifiBatteryStats()"

This reverts commit f4158fd258.

Reason for revert: Failure of com.android.internal.telephony.metrics.TelephonyMetricsTest tests

Change-Id: I254658e30459f97f2d3988e4abaff1456a668cef

services/core/java/com/android/server/am/BatteryStatsService.java

@@ -2499,7 +2499,6 @@ public final class BatteryStatsService extends IBatteryStats.Stub
      * @hide
      */
     public CellularBatteryStats getCellularBatteryStats() {
-        enforceCallingPermission();
         // Wait for the completion of pending works if there is any
         awaitCompletion();
         synchronized (mStats) {
@@ -2512,7 +2511,6 @@ public final class BatteryStatsService extends IBatteryStats.Stub
      * @hide
      */
     public WifiBatteryStats getWifiBatteryStats() {
-        enforceCallingPermission();
         // Wait for the completion of pending works if there is any
         awaitCompletion();
         synchronized (mStats) {