[Battery usage U] Create a flag to guard battery usage features

Bug: 261800937
Fix: 261800937
Test: manual
Change-Id: I891c235228c9ca0709471b496e6f75167fd0a126

tests/robotests/src/com/android/settings/fuelgauge/PowerUsageFeatureProviderImplTest.java

@@ -62,6 +62,11 @@ public class PowerUsageFeatureProviderImplTest {
         mPowerFeatureProvider.mPackageManager = mPackageManager;
     }
 
+    @Test
+    public void testIsBatteryUsageEnabled_returnFalse() {
+        assertThat(mPowerFeatureProvider.isBatteryUsageEnabled(mContext)).isTrue();
+    }
+
     @Test
     public void testIsTypeSystem_uidRoot_returnTrue() {
         assertThat(mPowerFeatureProvider.isTypeSystem(Process.ROOT_UID, null)).isTrue();