Add a custom Robolectric testrunner.

build/android/pylib/junit/test_runner.py

Index: build/android/pylib/junit/test_runner.py
diff --git a/build/android/pylib/junit/test_runner.py b/build/android/pylib/junit/test_runner.py
index 35ac666fae887bc82c257893872a730cf5567b2c..b85967b40d444d6ad7fa50c102c936085d0f7e2b 100644
--- a/build/android/pylib/junit/test_runner.py
+++ b/build/android/pylib/junit/test_runner.py
@@ -22,9 +22,13 @@ class JavaTestRunner(object):
 
   def RunTest(self, _test):
     """Runs junit tests from |self._test_suite|."""
+
     command = ['java',
+               '-Drobolectric.dependency.dir=%s' %
+                    os.path.join(constants.GetOutDirectory(), 'lib.java'),

[kzaikin, 2015/03/12 10:44:34]

You can calculate os.path.join(constants.GetOutDirectory(), 'lib.java') just
once

[mikecase (-- gone --), 2015/03/13 16:21:45]

Since we only calculate that path twice, I think its cleaner as is than storing
that path in a local variable.

                '-jar', os.path.join(constants.GetOutDirectory(), 'lib.java',
                                     '%s.jar' % self._test_suite)]
+
     if self._test_filter:
       command.extend(['-gtest-filter', self._test_filter])
     if self._package_filter: