export Java variables to Bazel

Test: build/bazel/bp2build.sh
Change-Id: Ia06f9265c9f96e6add6edbd0cee925fe37b430d3
diff --git a/bp2build/conversion_test.go b/bp2build/conversion_test.go
index d65ece8..e49d855 100644
--- a/bp2build/conversion_test.go
+++ b/bp2build/conversion_test.go
@@ -95,6 +95,14 @@
 			basename: "constants.bzl",
 		},
 		{
+			dir:      "java_toolchain",
+			basename: GeneratedBuildFileName,
+		},
+		{
+			dir:      "java_toolchain",
+			basename: "constants.bzl",
+		},
+		{
 			dir:      "metrics",
 			basename: "converted_modules.txt",
 		},