Move the job scheduler service code to its own jar file.

- Also remove the dependency from SystemServiceRegistry to JobScheduler

See apex/jobscheduler/README_js-mainline.md for the details.

Bug: 137763703
Test: build and boot
Test: atest CtsJobSchedulerTestCases
Change-Id: I2386c78b7a6085d6e543a63f22cb620c4cabd06a
diff --git a/services/tests/servicestests/Android.bp b/services/tests/servicestests/Android.bp
index 0614b3a..b37e460 100644
--- a/services/tests/servicestests/Android.bp
+++ b/services/tests/servicestests/Android.bp
@@ -40,6 +40,7 @@
         "hamcrest-library",
         "servicestests-utils",
         "xml-writer-device-lib",
+        "jobscheduler-service",
     ],
 
     aidl: {