Close exclusive fp on open exception

Tests/test_bmp_reference.py

@@ -17,12 +17,16 @@ class TestBmpReference(PillowTestCase):
         """ These shouldn't crash/dos, but they shouldn't return anything
         either """
         for f in self.get_files('b'):
+            def open(f):
                 try:
                     im = Image.open(f)
                     im.load()
                 except Exception:  # as msg:
                     pass
 
+            # Assert that there is no unclosed file warning
+            self.assert_warning(None, open, f)
+
     def test_questionable(self):
         """ These shouldn't crash/dos, but it's not well defined that these
         are in spec """

src/PIL/Image.py

@@ -2641,6 +2641,10 @@ def open(fp, mode="r"):
                 # opening failures that are entirely expected.
                 # logger.debug("", exc_info=True)
                 continue
+            except Exception:
+                if exclusive_fp:
+                    fp.close()
+                raise
         return None
 
     im = _open_core(fp, filename, prefix)