Add test data for mojo instrumentation tests.

R=navabi@chromium.org

Review URL: https://codereview.chromium.org/517983002

Cr-Commit-Position: refs/heads/master@{#292854}

build/android/buildbot/bb_device_steps.py

@@ -214,7 +214,7 @@ def RunMojoTests(options):
            None,
            'org.chromium.mojo.tests',
            'MojoTest',
-           None)
+           'bindings:mojo/public/interfaces/bindings/tests/data')
   RunInstrumentationSuite(options, test)