Add tests for covering all modified code (aio-libs#4630)

tests/test_http_parser.py

@@ -866,6 +866,27 @@ async def test_parse_chunked_payload_split_end_trailers2(self,
         assert out.is_eof()
         assert b'asdf' == b''.join(out._buffer)
 
+    async def test_parse_chunked_payload_split_end_trailers3(self,
+                                                             protocol) -> None:
+        out = aiohttp.StreamReader(protocol, loop=None)
+        p = HttpPayloadParser(out, chunked=True)
+        p.feed_data(b'4\r\nasdf\r\n0\r\nContent-MD5: ')
+        p.feed_data(b'912ec803b2ce49e4a541068d495ab570\r\n\r\n')
+
+        assert out.is_eof()
+        assert b'asdf' == b''.join(out._buffer)
+
+    async def test_parse_chunked_payload_split_end_trailers4(self,
+                                                             protocol) -> None:
+        out = aiohttp.StreamReader(protocol, loop=None)
+        p = HttpPayloadParser(out, chunked=True)
+        p.feed_data(b'4\r\nasdf\r\n0\r\n'
+                    b'C')
+        p.feed_data(b'ontent-MD5: 912ec803b2ce49e4a541068d495ab570\r\n\r\n')
+
+        assert out.is_eof()
+        assert b'asdf' == b''.join(out._buffer)
+
     async def test_http_payload_parser_length(self, stream) -> None:
         out = aiohttp.FlowControlDataQueue(stream,
                                            loop=asyncio.get_event_loop())