Uniformize OwlViT and Owlv2 processors (#35700)

* uniformize owlvit processor

* uniformize owlv2

* nit

* add positional arg test owlvit

* run-slow: owlvit, owlv2

* run-slow: owlvit, owlv2

* remove one letter variable

tests/models/owlv2/test_processor_owlv2.py

@@ -0,0 +1,38 @@
+import shutil
+import tempfile
+import unittest
+
+import pytest
+
+from transformers import Owlv2Processor
+from transformers.testing_utils import require_scipy
+
+from ...test_processing_common import ProcessorTesterMixin
+
+
+@require_scipy
+class Owlv2ProcessorTest(ProcessorTesterMixin, unittest.TestCase):
+    processor_class = Owlv2Processor
+
+    def setUp(self):
+        self.tmpdirname = tempfile.mkdtemp()
+        processor = self.processor_class.from_pretrained("google/owlv2-base-patch16-ensemble")
+        processor.save_pretrained(self.tmpdirname)
+
+    def tearDown(self):
+        shutil.rmtree(self.tmpdirname)
+
+    def test_processor_query_images_positional(self):
+        processor_components = self.prepare_components()
+        processor = Owlv2Processor(**processor_components)
+
+        image_input = self.prepare_image_inputs()
+        query_images = self.prepare_image_inputs()
+
+        inputs = processor(None, image_input, query_images)
+
+        self.assertListEqual(list(inputs.keys()), ["query_pixel_values", "pixel_values"])
+
+        # test if it raises when no input is passed
+        with pytest.raises(ValueError):
+            processor()