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/cmd/soong_build/queryview_test.go b/cmd/soong_build/queryview_test.go
index 675b532..525802a 100644
--- a/cmd/soong_build/queryview_test.go
+++ b/cmd/soong_build/queryview_test.go
@@ -234,9 +234,9 @@
 
 	for _, testCase := range testCases {
 		config := android.TestConfig(buildDir, nil, testCase.bp, nil)
-		ctx := android.NewTestContext()
+		ctx := android.NewTestContext(config)
 		ctx.RegisterModuleType("custom", customModuleFactory)
-		ctx.Register(config)
+		ctx.Register()
 
 		_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 		android.FailIfErrored(t, errs)