Fixed test case that fails because of string order.

Test: m -j32 FrameworksCoreTests &&  adb install -r -g
${ANDROID_PRODUCT_OUT}/data/app/FrameworksCoreTests/FrameworksCoreTests.apk
&& adb shell am instrument -e class
"android.net.NetworkPolicyManagerTest" -w
"com.android.frameworks.coretests/android.support.test.runner.AndroidJUnitRunner"

BUG: 28791717
Change-Id: Iaef6d8f1a82c6ab4af88f71e5b9e42e0386ed512