Fix the ART Buildbots using the master-art manifest.

When system/core/base/include/android-base is missing, create it as a
symlink to system/core/base/include/base.

This change is very brittle and is only to unblock the ART Buildbots.
It should be a temporary solution while we come up with something
better.

Bug: 26051370
Change-Id: Ie412fbf170e2cd260f77caaeb7af0b2e399ef3ab
diff --git a/tools/buildbot-build.sh b/tools/buildbot-build.sh
index 02787fb..37b4c48 100755
--- a/tools/buildbot-build.sh
+++ b/tools/buildbot-build.sh
@@ -45,6 +45,14 @@
   fi
 done
 
+# Workaround for b/26051370.
+#
+# system/core/base/include/base has been renamed to
+# system/core/base/include/android-base, but the master-art manifest
+# is pinned to an older revision for system/core; create this symlink
+# by hand to fix include paths.
+test -e system/core/base/include/android-base || ln -s base system/core/base/include/android-base
+
 if [[ $mode == "host" ]]; then
   make_command="make $j_arg $showcommands build-art-host-tests $common_targets ${out_dir}/host/linux-x86/lib/libjavacoretests.so ${out_dir}/host/linux-x86/lib64/libjavacoretests.so"
 elif [[ $mode == "target" ]]; then