Merge pull request #499 from wiredfool/webp_exif

*  Don't send None as exif to JpegImagePlugin._getexif -- homm 
*  Test for fix -- wiredfool

PIL/WebPImagePlugin.py

@@ -32,7 +32,9 @@ class WebPImageFile(ImageFile.ImageFile):
     def _open(self):
         data, width, height, self.mode, icc_profile, exif = _webp.WebPDecode(self.fp.read())
 
+        if icc_profile:
             self.info["icc_profile"] = icc_profile
+        if exif:
             self.info["exif"] = exif
 
         self.size = width, height

Tests/test_file_webp_metadata.py

@@ -82,3 +82,20 @@ def test_write_icc_metadata():
     assert_true(webp_icc_profile)
     if webp_icc_profile:
         assert_equal(webp_icc_profile, expected_icc_profile, "Webp ICC didn't match")
+
+
+def test_read_no_exif():
+    file_path = "Tests/images/flower.jpg"
+    image = Image.open(file_path)
+    expected_exif = image.info['exif']
+
+    buffer = BytesIO()
+
+    image.save(buffer, "webp")
+    
+    buffer.seek(0)
+    webp_image = Image.open(buffer)
+
+    assert_false(webp_image._getexif())
+    
+