title: gtest dependency for Bazel java_tools build?
body: <p>I am trying to follow the instructions for contributors here:</p>
  
  <p><a href="https://bazel.build/contributing.html" rel="nofollow noreferrer">https://bazel.build/contributing.html</a></p>
  
  <p>I have a successful build off of master (i.e. bazel build //src:bazel), but the doc suggests also "you might want to build the various tools Bazel uses." I am trying to do that, for example:</p>
  
  <pre><code>cd src/java_tools/singlejar
  bazel build //...
  </code></pre>
  
  <p>but it fails with:</p>
  
  <pre><code>ERROR: /Users/.../bazel/third_party/protobuf/3.2.0/BUILD:621:1: no such target '//external:gtest': target 'gtest' not declared in package 'external' defined by /Users/plaird/scone/public/bazel/WORKSPACE and referenced by '//third_party/protobuf/3.2.0:test_plugin'.
  </code></pre>
  
  <p>Do I need to build gtest locally, and then add it to the WORKSPACE file?</p>