Make system_server stubs consistent with other stubs

Include the module_api stubs in system_server one instead of
putting both of these jars on the classpath. Also rename it
to be in line with the other stubs.

Bug: 149293194
Test: m
Change-Id: Iead5af4152a49cd59a4fd7afc0312c2f0c872c1e

java/java.go

@@ -841,7 +841,7 @@ func (m *Module) getLinkType(name string) (ret linkType, stubs bool) {
 		return javaModule, true
 	case ver.kind == sdkModule:
 		return javaModule, false
-	case name == "services-stubs":
+	case name == "android_system_server_stubs_current":
 		return javaSystemServer, true
 	case ver.kind == sdkSystemServer:
 		return javaSystemServer, false