Prepare for removal of legacy-test from default targets

In preparation for removing junit classes from the Android API
the legacy-test target will be removed from the
TARGET_DEFAULT_JAVA_LIBRARIES. This change adds explicit
dependencies on junit and/or legacy-android-test to ensure that
modules will compile properly once it is removed.

Bug: 30188076
Test: make checkbuild
Change-Id: I0f34fe97154240e8f8eef6816df1c794da60351e
diff --git a/tests/cts/net/Android.mk b/tests/cts/net/Android.mk
index 4a77640..98cde9b 100644
--- a/tests/cts/net/Android.mk
+++ b/tests/cts/net/Android.mk
@@ -34,8 +34,14 @@
 
 LOCAL_PACKAGE_NAME := CtsNetTestCases
 
-LOCAL_STATIC_JAVA_LIBRARIES := core-tests-support  compatibility-device-util \
-                               ctstestrunner ctstestserver mockwebserver
+LOCAL_STATIC_JAVA_LIBRARIES := \
+    core-tests-support \
+    compatibility-device-util \
+    ctstestrunner \
+    ctstestserver \
+    mockwebserver \
+    junit \
+    legacy-android-test
 
 # uncomment when b/13249961 is fixed
 #LOCAL_SDK_VERSION := current