Provide min sdk version as ApiLevel instead of string.

Bug: 377723687
Test: Unit tests and compare the ninja and mk files generated.
Change-Id: I8c7b3b493877a9857ca433b015e6e49ad8387f91
diff --git a/apex/builder.go b/apex/builder.go
index 03a0bb9..8427719 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -1132,10 +1132,9 @@
 			depInfos[to.Name()] = info
 		} else {
 			toMinSdkVersion := "(no version)"
-			if info, ok := android.OtherModuleProvider(ctx, to, android.CommonModuleInfoKey); ok {
-				if v := info.MinSdkVersion; v != "" {
-					toMinSdkVersion = v
-				}
+			if info, ok := android.OtherModuleProvider(ctx, to, android.CommonModuleInfoKey); ok &&
+				!info.MinSdkVersion.IsPlatform && info.MinSdkVersion.ApiLevel != nil {
+				toMinSdkVersion = info.MinSdkVersion.ApiLevel.String()
 			}
 			depInfos[to.Name()] = android.ApexModuleDepInfo{
 				To:            to.Name(),