Dexopt service-connectivity.

`service-connectivity` is a jar that system_server loads dynamically.
Such jars can be dexopted now. This CL adds `service-connectivity` to a
`systemserverclasspath_fragment`, which does not actually add the jar to
the classpath, but tells the build system to dexopt it.

NOTE: The corresponding `exported_systemserverclasspath_fragments` needs
to be added to the `prebuilt_apex` once a new prebuilt is dropped.

Bug: 203198541
Test: m com.android.tethering
Change-Id: I53745baaf1bc7142cc12a1e6cd8d84c9b338ac9d
Merged-In: I53745baaf1bc7142cc12a1e6cd8d84c9b338ac9d
Merged-In: I9a009493fe0482967ab1f92516514715cfd457d6

Tethering/Android.bp

@@ -206,4 +206,5 @@ android_app {
 sdk {
     name: "tethering-module-sdk",
     bootclasspath_fragments: ["com.android.tethering-bootclasspath-fragment"],
+    systemserverclasspath_fragments: ["com.android.tethering-systemserverclasspath-fragment"],
 }

Tethering/apex/Android.bp

@@ -44,8 +44,8 @@ apex {
     bootclasspath_fragments: [
         "com.android.tethering-bootclasspath-fragment",
     ],
-    java_libs: [
-        "service-connectivity",
+    systemserverclasspath_fragments: [
+        "com.android.tethering-systemserverclasspath-fragment",
     ],
     multilib: {
         first: {
@@ -114,6 +114,12 @@ bootclasspath_fragment {
     },
 }
 
+systemserverclasspath_fragment {
+    name: "com.android.tethering-systemserverclasspath-fragment",
+    standalone_contents: ["service-connectivity"],
+    apex_available: ["com.android.tethering"],
+}
+
 override_apex {
     name: "com.android.tethering.inprocess",
     base: "com.android.tethering",