Add java.RegisterRequiredBuildComponentsForTest function

Insulate tests that exercise code in the java package from having to
register the build components provided by the java package by providing
a single function that registers them all. This follows the pattern
currently used in the cc and rust packages.

This change is in preparation for switching the dex_bootjars singleton
from a singleton, which does not require a module definition in order
to be instantiated, to a singleton module which does. That will require
adding a module definition into java.GatherRequiredDepsForTest() and
this change ensures that the required components will have been
registered in every test.

Bug: 177892522
Test: m nothing
Change-Id: I6475db8240894947dd07c89a940a3e4f201aa598
diff --git a/sdk/testing.go b/sdk/testing.go
index 38755a9..1ac873b 100644
--- a/sdk/testing.go
+++ b/sdk/testing.go
@@ -107,12 +107,7 @@
 	ctx.PostDepsMutators(android.RegisterVisibilityRuleEnforcer)
 
 	// from java package
-	java.RegisterJavaBuildComponents(ctx)
-	java.RegisterAppBuildComponents(ctx)
-	java.RegisterSdkLibraryBuildComponents(ctx)
-	java.RegisterPrebuiltApisBuildComponents(ctx)
-	java.RegisterStubsBuildComponents(ctx)
-	java.RegisterSystemModulesBuildComponents(ctx)
+	java.RegisterRequiredBuildComponentsForTest(ctx)
 
 	// from cc package
 	cc.RegisterRequiredBuildComponentsForTest(ctx)