tests: Expose test's fake_header.h so py_cc_toolchain tests can use it. (#1388)
Newer Bazel versions default to not exporting files by default; this
explicitly exports the file so it can be referenced.
diff --git a/tests/cc/BUILD.bazel b/tests/cc/BUILD.bazel
index 876d163..3f7925d 100644
--- a/tests/cc/BUILD.bazel
+++ b/tests/cc/BUILD.bazel
@@ -19,6 +19,8 @@
package(default_visibility = ["//:__subpackages__"])
+exports_files(["fake_header.h"])
+
toolchain(
name = "fake_py_cc_toolchain",
tags = PREVENT_IMPLICIT_BUILDING_TAGS,
