Pass Config to NewTestContext instead of ctx.Register

Prepare for using Config when adding singletons by passing
Config to NewTestContext and NewContext instead of to ctx.Register.
This will enable a followup change to store SingletonMakeVarsProviders
registered on the Context in the Config, which is necessary to run
multiple tests in parallel without data races.

Test: all soong tests
Change-Id: Id229629a4e42ff4487d317241673837726c075fc
diff --git a/etc/prebuilt_etc_test.go b/etc/prebuilt_etc_test.go
index 8fc36c2..6c4c0b6 100644
--- a/etc/prebuilt_etc_test.go
+++ b/etc/prebuilt_etc_test.go
@@ -58,7 +58,7 @@
 
 	config := android.TestArchConfig(buildDir, nil, bp, fs)
 
-	ctx := android.NewTestArchContext()
+	ctx := android.NewTestArchContext(config)
 	ctx.RegisterModuleType("prebuilt_etc", PrebuiltEtcFactory)
 	ctx.RegisterModuleType("prebuilt_etc_host", PrebuiltEtcHostFactory)
 	ctx.RegisterModuleType("prebuilt_usr_share", PrebuiltUserShareFactory)
@@ -66,7 +66,7 @@
 	ctx.RegisterModuleType("prebuilt_font", PrebuiltFontFactory)
 	ctx.RegisterModuleType("prebuilt_firmware", PrebuiltFirmwareFactory)
 	ctx.RegisterModuleType("prebuilt_dsp", PrebuiltDSPFactory)
-	ctx.Register(config)
+	ctx.Register()
 
 	return ctx, config
 }