Add deps builder mapping for yosemite port.

Tools/Scripts/webkitpy/layout_tests/port/builders_unittest.py

Index: Tools/Scripts/webkitpy/layout_tests/port/builders_unittest.py
diff --git a/Tools/Scripts/webkitpy/layout_tests/port/builders_unittest.py b/Tools/Scripts/webkitpy/layout_tests/port/builders_unittest.py
index d5ba2f2f5e09f92568cf1ac0f496af24070244bf..6235bc64f33b3cc661541a51f42aa8b65f7840c0 100644
--- a/Tools/Scripts/webkitpy/layout_tests/port/builders_unittest.py
+++ b/Tools/Scripts/webkitpy/layout_tests/port/builders_unittest.py
@@ -40,3 +40,8 @@ class BuildersTest(unittest.TestCase):
         }
         for name, expected in tests.items():
             self.assertEqual(expected, builders.builder_path_from_name(name))
+
+    def test_deps_builder_mappings(self):
+        for port_name in builders.all_port_names():
+            if port_name != 'android':
+                self.assertIsNotNone(builders.deps_builder_name_for_port_name(port_name))