Fix type assertion error regarding dex_import

Ida6f7bb784efe74cc1fa0e8d370eaee803f08b0f made it possible to add
dex_import modules into apex, but that change had a bug. When creating
Android.mk for the dex_import module, the code executed an unchecked
type assertion to convert java.DexImport to java.Dependency, which
cannot be successful. This change fixes the bug by doing a checked type
assertion instead.

Exempt-From-Owner-Approval: cp from AOSP

Bug: 157886942
Test: m (test added)
Merged-In: Id22c20d42effce539fab10b0d349bf340d467f02
(cherry picked from commit 9e83f0b531)
Change-Id: Id22c20d42effce539fab10b0d349bf340d467f02

apex/apex_test.go

@@ -291,7 +291,7 @@ func ensureListEmpty(t *testing.T, result []string) {
 
 // Minimal test
 func TestBasicApex(t *testing.T) {
-	ctx, _ := testApex(t, `
+	ctx, config := testApex(t, `
 		apex_defaults {
 			name: "myapex-defaults",
 			manifest: ":myapex.manifest",
@@ -446,6 +446,16 @@ func TestBasicApex(t *testing.T) {
 
 	apexRule := ctx.ModuleForTests("myapex", "android_common_myapex_image").Rule("apexRule")
 
+	// Make sure that Android.mk is created
+	ab := ctx.ModuleForTests("myapex", "android_common_myapex_image").Module().(*apexBundle)
+	data := android.AndroidMkDataForTest(t, config, "", ab)
+	var builder strings.Builder
+	data.Custom(&builder, ab.BaseModuleName(), "TARGET_", "", data)
+
+	androidMk := builder.String()
+	ensureContains(t, androidMk, "LOCAL_MODULE := mylib.myapex\n")
+	ensureNotContains(t, androidMk, "LOCAL_MODULE := mylib.com.android.myapex\n")
+
 	optFlags := apexRule.Args["opt_flags"]
 	ensureContains(t, optFlags, "--pubkey vendor/foo/devkeys/testkey.avbpubkey")
 	// Ensure that the NOTICE output is being packaged as an asset.