Revert of Remove mojo test step from bb_device_steps.py

build/android/buildbot/bb_device_steps.py

Index: build/android/buildbot/bb_device_steps.py
diff --git a/build/android/buildbot/bb_device_steps.py b/build/android/buildbot/bb_device_steps.py
index 6a7c90bcc7e4a61b9a90148b842fa545e6149fd3..59dd94ce9b92e93df950d3620811a7000d437f79 100755
--- a/build/android/buildbot/bb_device_steps.py
+++ b/build/android/buildbot/bb_device_steps.py
@@ -75,7 +75,7 @@
       'webview:android_webview/test/data/device_files'),
     ])
 
-VALID_TESTS = set(['chromedriver', 'chrome_proxy', 'gpu', 'sync',
+VALID_TESTS = set(['chromedriver', 'chrome_proxy', 'gpu', 'mojo', 'sync',
                    'telemetry_perf_unittests', 'ui', 'unit', 'webkit',
                    'webkit_layout', 'python_unittests'])
 
@@ -206,6 +206,20 @@
     args = args + ['--device', devices[0]]
   bb_annotations.PrintNamedStep('telemetry_perf_unittests')
   RunCmd(['tools/perf/run_tests'] + args)
+
+
+def RunMojoTests(options):
+  """Runs the mojo unit tests.
+
+  Args:
+    options: options object.
+  """
+  test = I('MojoTest',
+           None,
+           'org.chromium.mojo.tests',
+           'MojoTest',
+           'bindings:mojo/public/interfaces/bindings/tests/data')
+  RunInstrumentationSuite(options, test)
 
 
 def InstallApk(options, test, print_step=False):
@@ -531,6 +545,7 @@
       ('chromedriver', RunChromeDriverTests),
       ('chrome_proxy', RunChromeProxyTests),
       ('gpu', RunGPUTests),
+      ('mojo', RunMojoTests),
       ('python_unittests', RunPythonUnitTests),
       ('sync', RunChromeSyncShellTests),
       ('telemetry_perf_unittests', RunTelemetryPerfUnitTests),