Remove implementation details from tethering hidden api flags

Ran the following to compute the set of split_packages and
package_prefixes properties.
    m analyze_bcpf &&
    analyze_bcpf --bcpf com.android.tethering-bootclasspath-fragment --apex framework-tethering --sdk tethering-module-sdk

Ignore-AOSP-First: AOSP change breaks in tm-dev due to missing android.nearby package
Bug: 194063708
Test: m out/soong/hiddenapi/hiddenapi-flags.csv
Change-Id: Iaa1207799a44ab892dc30b55f363c6e7deb94d86
diff --git a/Tethering/apex/Android.bp b/Tethering/apex/Android.bp
index b709693..b9f7a54 100644
--- a/Tethering/apex/Android.bp
+++ b/Tethering/apex/Android.bp
@@ -132,15 +132,43 @@
     hidden_api: {
         max_target_r_low_priority: [
             "hiddenapi/hiddenapi-max-target-r-loprio.txt",
-	],
+        ],
         max_target_o_low_priority: [
             "hiddenapi/hiddenapi-max-target-o-low-priority.txt",
             "hiddenapi/hiddenapi-max-target-o-low-priority-tiramisu.txt",
-	],
+        ],
         unsupported: [
             "hiddenapi/hiddenapi-unsupported.txt",
             "hiddenapi/hiddenapi-unsupported-tiramisu.txt",
         ],
+
+        // The following packages contain classes from other modules on the
+        // bootclasspath. That means that the hidden API flags for this module
+        // has to explicitly list every single class this module provides in
+        // that package to differentiate them from the classes provided by other
+        // modules. That can include private classes that are not part of the
+        // API.
+        split_packages: [
+            "android.app.usage",
+            "android.nearby",
+            "android.net",
+            "android.net.netstats",
+            "android.net.util",
+        ],
+
+        // The following packages and all their subpackages currently only
+        // contain classes from this bootclasspath_fragment. Listing a package
+        // here won't prevent other bootclasspath modules from adding classes in
+        // any of those packages but it will prevent them from adding those
+        // classes into an API surface, e.g. public, system, etc.. Doing so will
+        // result in a build failure due to inconsistent flags.
+        package_prefixes: [
+            "android.nearby.aidl",
+            "android.net.apf",
+            "android.net.connectivity",
+            "android.net.netstats.provider",
+            "android.net.nsd",
+        ],
     },
 }