Rename the empty_jar() rule to be minimal_jar() since the jar file is no longer empty

Change-Id: I9a5fc75ecf30c4c63632113b79405fd28d1daa5e
diff --git a/tools/build/bazel/minimal_jar.bzl b/tools/build/bazel/minimal_jar.bzl
new file mode 100644
index 0000000..ccc0c65
--- /dev/null
+++ b/tools/build/bazel/minimal_jar.bzl
@@ -0,0 +1,31 @@
+# Copyright 2015 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+def _impl(ctx):
+    jar = ctx.outputs.jar
+
+    cmd = [
+        "mkdir readme && touch readme/README && jar cf %s readme/README" % (jar.path),
+    ]
+
+    ctx.action(
+        outputs = [jar],
+        progress_message = "Generating minimal jar for %s" % ctx.attr.name,
+        command = ";\n".join(cmd),
+    )
+
+minimal_jar = rule(
+    implementation = _impl,
+    outputs = {"jar": "%{name}.jar"},
+)