Export apex_available_baseline to soong_injection

So that it can be used in the bazel implementation.

Bug: 268006095
Test: m nothing, check that it's in out/soong/soong_injection
Change-Id: I1520dd874076dee7fa083648d0790b060d658e5a
diff --git a/bp2build/bp2build.go b/bp2build/bp2build.go
index 86b9b27..062eba8 100644
--- a/bp2build/bp2build.go
+++ b/bp2build/bp2build.go
@@ -45,8 +45,12 @@
 	bp2buildFiles := CreateBazelFiles(ctx.Config(), nil, res.buildFileToTargets, ctx.mode)
 	writeFiles(ctx, bp2buildDir, bp2buildFiles)
 
-	soongInjectionDir := android.PathForOutput(ctx, bazel.SoongInjectionDirName)
-	writeFiles(ctx, soongInjectionDir, CreateSoongInjectionDirFiles(ctx, res.metrics))
+	injectionFiles, err := CreateSoongInjectionDirFiles(ctx, res.metrics)
+	if err != nil {
+		fmt.Printf("%s\n", err.Error())
+		os.Exit(1)
+	}
+	writeFiles(ctx, android.PathForOutput(ctx, bazel.SoongInjectionDirName), injectionFiles)
 
 	return &res.metrics
 }
@@ -55,17 +59,20 @@
 // This includes
 // 1. config value(s) that are hardcoded in Soong
 // 2. product_config variables
-func CreateSoongInjectionDirFiles(ctx *CodegenContext, metrics CodegenMetrics) []BazelFile {
+func CreateSoongInjectionDirFiles(ctx *CodegenContext, metrics CodegenMetrics) ([]BazelFile, error) {
 	var ret []BazelFile
 
 	productConfigFiles, err := CreateProductConfigFiles(ctx)
 	if err != nil {
-		fmt.Printf("ERROR: %s", err.Error())
-		os.Exit(1)
+		return nil, err
 	}
 	ret = append(ret, productConfigFiles...)
-	ret = append(ret, soongInjectionFiles(ctx.Config(), metrics)...)
-	return ret
+	injectionFiles, err := soongInjectionFiles(ctx.Config(), metrics)
+	if err != nil {
+		return nil, err
+	}
+	ret = append(ret, injectionFiles...)
+	return ret, nil
 }
 
 // Get the output directory and create it if it doesn't exist.
diff --git a/bp2build/conversion.go b/bp2build/conversion.go
index 5b3e19f..73df675 100644
--- a/bp2build/conversion.go
+++ b/bp2build/conversion.go
@@ -22,7 +22,7 @@
 }
 
 // PRIVATE: Use CreateSoongInjectionDirFiles instead
-func soongInjectionFiles(cfg android.Config, metrics CodegenMetrics) []BazelFile {
+func soongInjectionFiles(cfg android.Config, metrics CodegenMetrics) ([]BazelFile, error) {
 	var files []BazelFile
 
 	files = append(files, newFile("android", GeneratedBuildFileName, "")) // Creates a //cc_toolchain package.
@@ -36,7 +36,11 @@
 	files = append(files, newFile("java_toolchain", "constants.bzl", java_config.BazelJavaToolchainVars(cfg)))
 
 	files = append(files, newFile("apex_toolchain", GeneratedBuildFileName, "")) // Creates a //apex_toolchain package.
-	files = append(files, newFile("apex_toolchain", "constants.bzl", apex.BazelApexToolchainVars()))
+	apexToolchainVars, err := apex.BazelApexToolchainVars()
+	if err != nil {
+		return nil, err
+	}
+	files = append(files, newFile("apex_toolchain", "constants.bzl", apexToolchainVars))
 
 	files = append(files, newFile("metrics", "converted_modules.txt", strings.Join(metrics.Serialize().ConvertedModules, "\n")))
 
@@ -52,7 +56,7 @@
 
 	apiLevelsContent, err := json.Marshal(android.GetApiLevelsMap(cfg))
 	if err != nil {
-		panic(err)
+		return nil, err
 	}
 	files = append(files, newFile("api_levels", GeneratedBuildFileName, `exports_files(["api_levels.json"])`))
 	files = append(files, newFile("api_levels", "api_levels.json", string(apiLevelsContent)))
@@ -64,7 +68,7 @@
 	files = append(files, newFile("allowlists", "mixed_build_prod_allowlist.txt", strings.Join(android.GetBazelEnabledModules(android.BazelProdMode), "\n")+"\n"))
 	files = append(files, newFile("allowlists", "mixed_build_staging_allowlist.txt", strings.Join(android.GetBazelEnabledModules(android.BazelStagingMode), "\n")+"\n"))
 
-	return files
+	return files, nil
 }
 
 func CreateBazelFiles(
diff --git a/bp2build/conversion_test.go b/bp2build/conversion_test.go
index 8c24093..8c1d2ae 100644
--- a/bp2build/conversion_test.go
+++ b/bp2build/conversion_test.go
@@ -84,8 +84,10 @@
 
 func TestCreateBazelFiles_Bp2Build_CreatesDefaultFiles(t *testing.T) {
 	testConfig := android.TestConfig("", make(map[string]string), "", make(map[string][]byte))
-	files := soongInjectionFiles(testConfig, CreateCodegenMetrics())
-
+	files, err := soongInjectionFiles(testConfig, CreateCodegenMetrics())
+	if err != nil {
+		t.Error(err)
+	}
 	expectedFilePaths := []bazelFilepath{
 		{
 			dir:      "android",