Expose getCapabilities

Expose getCapabilities() for EthernetNetworkFactory.

Bug: 182963415
Test: m ethernet-service
Change-Id: I430416af8fae3d4ee99f2f2abe529e3051e9e5cb

framework/api/current.txt

@@ -291,6 +291,7 @@ package android.net {
     ctor public NetworkCapabilities();
     ctor public NetworkCapabilities(android.net.NetworkCapabilities);
     method public int describeContents();
+    method @NonNull public int[] getCapabilities();
     method public int getLinkDownstreamBandwidthKbps();
     method public int getLinkUpstreamBandwidthKbps();
     method @Nullable public android.net.NetworkSpecifier getNetworkSpecifier();

framework/src/android/net/NetworkCapabilities.java

@@ -609,10 +609,8 @@ public final class NetworkCapabilities implements Parcelable {
      * Gets all the capabilities set on this {@code NetworkCapability} instance.
      *
      * @return an array of capability values for this instance.
-     * @hide
      */
-    @UnsupportedAppUsage
-    public @NetCapability int[] getCapabilities() {
+    public @NonNull @NetCapability int[] getCapabilities() {
         return NetworkCapabilitiesUtils.unpackBits(mNetworkCapabilities);
     }