Cannot find gcov or GCOV with Bazel 0.17.1

[cushon]

Building Android Studio with Bazel 0.17.1 fails with the following error:

ERROR: in target '//external:cc_toolchain': no such package '@local_config_cc//': Traceback (most recent call last):
        File "external/bazel_tools/tools/cpp/cc_configure.bzl", line 56
                configure_unix_toolchain(repository_ctx, cpu_value, overriden...)
        File "external/bazel_tools/tools/cpp/unix_cc_configure.bzl", line 486, in configure_unix_toolchain
                _find_generic(repository_ctx, "gcov", "GCOV", overri...)
        File "external/bazel_tools/tools/cpp/unix_cc_configure.bzl", line 465, in _find_generic
                auto_configure_fail(msg)
        File "external/bazel_tools/tools/cpp/lib_cc_configure.bzl", line 109, in auto_configure_fail
                fail(("\n%sAuto-Configuration Error:%...)))

Auto-Configuration Error: Cannot find gcov or GCOV; either correct your path or set the GCOV environment variable

[cushon]

This was a regression introduced by a95a442 and fixed in 1d956c7 (which didn't make the baseline for 0.17.1).

[cushon]

This will be fixed in 0.17.2 (#6164 (comment)) and 0.18x.