eclass: temp fix to use bazel.eclass with EAPI 6.

The Chrome OS build setup does not yet support ebuilds/eclasses that
include BDEPENDS. This change lets EAPI 6 ebuilds use bazel.eclass,
which will render its BDEPENDS statement inert.

This works in our case since Bazel is included in the CrOS SDK.

This change is temporary and can be reverted as soon as crbug.com/924701
is resolved.

BUG=chromium:955950
TEST=`emerge-chell tensorflow`

Change-Id: Ib8245f92ae497d953207455031c0d60f9e59ab6f
Reviewed-on: https://chromium-review.googlesource.com/1705657
Tested-by: Michael Martis <martis@chromium.org>
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-by: Andrew Moylan <amoylan@chromium.org>
diff --git a/eclass/bazel.eclass b/eclass/bazel.eclass
index ce80ea1..8801e9d 100644
--- a/eclass/bazel.eclass
+++ b/eclass/bazel.eclass
@@ -12,11 +12,12 @@
 #
 # This eclass does not export any phase functions.
 
+# TODO(chromium:924701): re-disable EAPI 6 support.
 case "${EAPI:-0}" in
-	0|1|2|3|4|5|6)
+	0|1|2|3|4|5)
 		die "Unsupported EAPI=${EAPI:-0} (too old) for ${ECLASS}"
 		;;
-	7)
+	6|7)
 		;;
 	*)
 		die "Unsupported EAPI=${EAPI} (unknown) for ${ECLASS}"