Make aconfig flags generate a library instead of a srcjar.

Also add unit tests for the rest of device_config

Bug: 283475679
Test: m nothing (soong unit tests)
Change-Id: Iee18a1f2f2cbb23e8c8d84c54e903b32be29a693
diff --git a/device_config/testing.go b/device_config/testing.go
index f054476..284a7fa 100644
--- a/device_config/testing.go
+++ b/device_config/testing.go
@@ -14,6 +14,16 @@
 
 package device_config
 
-import "android/soong/android"
+import (
+	"testing"
 
-var PrepareForTestWithSyspropBuildComponents = android.FixtureRegisterWithContext(registerBuildComponents)
+	"android/soong/android"
+)
+
+var PrepareForTestWithDeviceConfigBuildComponents = android.FixtureRegisterWithContext(registerBuildComponents)
+
+func runTest(t *testing.T, errorHandler android.FixtureErrorHandler, bp string) *android.TestResult {
+	return android.GroupFixturePreparers(PrepareForTestWithDeviceConfigBuildComponents).
+		ExtendWithErrorHandler(errorHandler).
+		RunTestWithBp(t, bp)
+}