For legacy10 APEXes default target_sdk_version and min_sdk_version to 29

Test: m com.android.conscrypt
Bug: 149733822
Change-Id: Ia863b5701716ef4022b470ee758368ea4fffb1d4
Merged-In: Ia863b5701716ef4022b470ee758368ea4fffb1d4
(cherry picked from commit db10c13bdf8bec1377406444c6a2f3e0c9f08277)
diff --git a/apex/builder.go b/apex/builder.go
index 88c7098..adb3219 100644
--- a/apex/builder.go
+++ b/apex/builder.go
@@ -383,6 +383,16 @@
 
 		targetSdkVersion := ctx.Config().DefaultAppTargetSdk()
 		minSdkVersion := ctx.Config().DefaultAppTargetSdk()
+
+		if proptools.Bool(a.properties.Legacy_android10_support) {
+			if !java.UseApiFingerprint(ctx, targetSdkVersion) {
+				targetSdkVersion = "29"
+			}
+			if !java.UseApiFingerprint(ctx, minSdkVersion) {
+				minSdkVersion = "29"
+			}
+		}
+
 		if java.UseApiFingerprint(ctx, targetSdkVersion) {
 			targetSdkVersion += fmt.Sprintf(".$$(cat %s)", java.ApiFingerprintPath(ctx).String())
 			implicitInputs = append(implicitInputs, java.ApiFingerprintPath(ctx))