Revert "Add method to read trunk stable flag"

This reverts commit b0f489021bae98b0b0874e80720bb73e1f36c478.

Reason for revert: Currently reading trunk stable flag from mainline module is not supported. So reverting the CL to avoid confusion.

Change-Id: I0db04f28f378399aa299b325312a6af7f45d4f67
diff --git a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
index 1714f28..e646f37 100644
--- a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
+++ b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
@@ -63,9 +63,6 @@
     @VisibleForTesting
     public static final long DEFAULT_PACKAGE_VERSION = 1000;
 
-    private static final String CORE_NETWORKING_TRUNK_STABLE_NAMESPACE = "android_core_networking";
-    private static final String CORE_NETWORKING_TRUNK_STABLE_FLAG_PACKAGE = "com.android.net.flags";
-
     @VisibleForTesting
     public static void resetPackageVersionCacheForTest() {
         sPackageVersion = -1;
@@ -417,31 +414,4 @@
 
         return pkgs.get(0).activityInfo.applicationInfo.packageName;
     }
-
-    /**
-     * Check whether one specific trunk stable flag in android_core_networking namespace is enabled.
-     * This method reads trunk stable feature flag value from DeviceConfig directly since
-     * java_aconfig_library soong module is not available in the mainline branch.
-     * After the mainline branch support the aconfig soong module, this function must be removed and
-     * java_aconfig_library must be used instead to check if the feature is enabled.
-     *
-     * @param flagName The name of the trunk stable flag
-     * @return true if this feature is enabled, or false if disabled.
-     */
-    public static boolean isTrunkStableFeatureEnabled(final String flagName) {
-        return isTrunkStableFeatureEnabled(
-                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
-                CORE_NETWORKING_TRUNK_STABLE_FLAG_PACKAGE,
-                flagName
-        );
-    }
-
-    private static boolean isTrunkStableFeatureEnabled(final String namespace,
-            final String packageName, final String flagName) {
-        return DeviceConfig.getBoolean(
-                namespace,
-                packageName + "." + flagName,
-                false /* defaultValue */
-        );
-    }
 }
diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java b/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
index befd751..5a96bcb 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
@@ -71,10 +71,6 @@
 public class DeviceConfigUtilsTest {
     private static final String TEST_NAME_SPACE = "connectivity";
     private static final String TEST_EXPERIMENT_FLAG = "experiment_flag";
-    private static final String CORE_NETWORKING_TRUNK_STABLE_NAMESPACE = "android_core_networking";
-    private static final String TEST_TRUNK_STABLE_FLAG = "trunk_stable_feature";
-    private static final String TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY =
-            "com.android.net.flags.trunk_stable_feature";
     private static final int TEST_FLAG_VALUE = 28;
     private static final String TEST_FLAG_VALUE_STRING = "28";
     private static final int TEST_DEFAULT_FLAG_VALUE = 0;
@@ -440,25 +436,4 @@
                                                eq(TEST_EXPERIMENT_FLAG)));
         assertFalse(DeviceConfigUtils.isNetworkStackFeatureNotChickenedOut(TEST_EXPERIMENT_FLAG));
     }
-
-    @Test
-    public void testIsCoreNetworkingTrunkStableFeatureEnabled() {
-        doReturn(null).when(() -> DeviceConfig.getProperty(
-                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
-                TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY));
-        assertFalse(DeviceConfigUtils.isTrunkStableFeatureEnabled(
-                TEST_TRUNK_STABLE_FLAG));
-
-        doReturn("false").when(() -> DeviceConfig.getProperty(
-                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
-                TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY));
-        assertFalse(DeviceConfigUtils.isTrunkStableFeatureEnabled(
-                TEST_TRUNK_STABLE_FLAG));
-
-        doReturn("true").when(() -> DeviceConfig.getProperty(
-                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
-                TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY));
-        assertTrue(DeviceConfigUtils.isTrunkStableFeatureEnabled(
-                TEST_TRUNK_STABLE_FLAG));
-    }
 }