message: [XLA] Skip float16 adam_tests.
  Adam tests compare the output of the computation against a hand wirtten numpy
  solution which does not take into account the precision and hence fail for
  float16.
diff: @@ -52,6 +52,8 @@ class AdamOptimizerTest(XLATestCase):
  def testBasic(self):
  for dtype in self.float_types:
  + if dtype == np.float16:
  + continue
  with self.test_session(), self.test_scope():
  variable_scope.get_variable_scope().set_use_resource(True)
  @@ -91,6 +93,8 @@ class AdamOptimizerTest(XLATestCase):
  def testTensorLearningRate(self):
  for dtype in self.float_types:
  + if dtype == np.float16:
  + continue
  with self.test_session(), self.test_scope():
  variable_scope.get_variable_scope().set_use_resource(True)
  @@ -130,6 +134,8 @@ class AdamOptimizerTest(XLATestCase):
  def testSharing(self):
  for dtype in self.float_types:
  + if dtype == np.float16:
  + continue
  with self.test_session(), self.test_scope():
  variable_scope.get_variable_scope().set_use_resource(True)
  