Support two active sdks in EffectiveVersionString

Currently it would return the default one even if the requested one is
an active sdk.

Bug: 270609292
Test: go test ./java
Test: built `rkpdapp` locally in internal and verified that its
targetSdkVersion is U and V
Test: TH

Change-Id: Idb03ff4786ff87fb7911bf31205941618a662404
diff --git a/android/sdk_version.go b/android/sdk_version.go
index 8953eae..a7e03dc 100644
--- a/android/sdk_version.go
+++ b/android/sdk_version.go
@@ -211,7 +211,29 @@
 	if !s.ApiLevel.IsPreview() {
 		return s.ApiLevel.String(), nil
 	}
-	return ctx.Config().DefaultAppTargetSdk(ctx).String(), nil
+	// Determine the default sdk
+	ret := ctx.Config().DefaultAppTargetSdk(ctx)
+	if !ret.IsPreview() {
+		// If the default sdk has been finalized, return that
+		return ret.String(), nil
+	}
+	// There can be more than one active in-development sdks
+	// If an app is targeting an active sdk, but not the default one, return the requested active sdk.
+	// e.g.
+	// SETUP
+	// In-development: UpsideDownCake, VanillaIceCream
+	// Default: VanillaIceCream
+	// Android.bp
+	// min_sdk_version: `UpsideDownCake`
+	// RETURN
+	// UpsideDownCake and not VanillaIceCream
+	for _, preview := range ctx.Config().PreviewApiLevels() {
+		if s.ApiLevel.String() == preview.String() {
+			return preview.String(), nil
+		}
+	}
+	// Otherwise return the default one
+	return ret.String(), nil
 }
 
 var (
diff --git a/java/app_test.go b/java/app_test.go
index c77f29d..5b16cea 100644
--- a/java/app_test.go
+++ b/java/app_test.go
@@ -1005,6 +1005,7 @@
 		platformSdkInt        int
 		platformSdkCodename   string
 		platformSdkFinal      bool
+		minSdkVersionBp       string
 		expectedMinSdkVersion string
 		platformApis          bool
 		activeCodenames       []string
@@ -1052,6 +1053,14 @@
 			platformSdkCodename:   "S",
 			activeCodenames:       []string{"S"},
 		},
+		{
+			name:                  "two active SDKs",
+			sdkVersion:            "module_current",
+			minSdkVersionBp:       "UpsideDownCake",
+			expectedMinSdkVersion: "UpsideDownCake", // And not VanillaIceCream
+			platformSdkCodename:   "VanillaIceCream",
+			activeCodenames:       []string{"UpsideDownCake", "VanillaIceCream"},
+		},
 	}
 
 	for _, moduleType := range []string{"android_app", "android_library"} {
@@ -1061,12 +1070,17 @@
 				if test.platformApis {
 					platformApiProp = "platform_apis: true,"
 				}
+				minSdkVersionProp := ""
+				if test.minSdkVersionBp != "" {
+					minSdkVersionProp = fmt.Sprintf(` min_sdk_version: "%s",`, test.minSdkVersionBp)
+				}
 				bp := fmt.Sprintf(`%s {
 					name: "foo",
 					srcs: ["a.java"],
 					sdk_version: "%s",
 					%s
-				}`, moduleType, test.sdkVersion, platformApiProp)
+					%s
+				}`, moduleType, test.sdkVersion, platformApiProp, minSdkVersionProp)
 
 				result := android.GroupFixturePreparers(
 					prepareForJavaTest,