CookieDecoder should handle empty domain as null, close AsyncHttpClient#806

Author: Stephane Landelle

api/src/main/java/org/asynchttpclient/cookie/KeyValuePairsParser.java

@@ -131,7 +131,7 @@ private void parse6(String header, int nameStart, String value) {
         char c5 = header.charAt(nameStart + 5);
 
         if (isDomain(c0, c1, c2, c3, c4, c5))
-            domain = value;
+            domain = value.isEmpty() ? null : value;
         else if (isSecure(c0, c1, c2, c3, c4, c5))
             secure = true;
     }

api/src/test/java/org/asynchttpclient/cookie/CookieDecoderTest.java

@@ -14,6 +14,7 @@
 
 import static org.testng.Assert.assertEquals;
 import static org.testng.Assert.assertNotNull;
+import static org.testng.Assert.assertNull;
 
 import org.testng.annotations.Test;
 
@@ -44,4 +45,10 @@ public void testDecodeQuotedContainingEscapedQuote() {
         assertEquals(cookie.getValue(), "VALUE1\"");
         assertEquals(cookie.getRawValue(), "\"VALUE1\\\"\"");
     }
+
+    @Test(groups = "fast")
+    public void testIgnoreEmptyDomain() {
+        Cookie cookie = CookieDecoder.decode("sessionid=OTY4ZDllNTgtYjU3OC00MWRjLTkzMWMtNGUwNzk4MTY0MTUw;Domain=;Path=/");
+        assertNull(cookie.getDomain());
+    }
 }