py3: remove extra encoding/decoding of url: pass it as bytes only when required

scrapy/core/downloader/handlers/http11.py

@@ -206,7 +206,7 @@ class ScrapyAgent(object):
         agent = self._get_agent(request, timeout)
 
         # request details
-        url = to_bytes(urldefrag(request.url)[0])
+        url = urldefrag(request.url)[0]
         method = to_bytes(request.method)
         headers = TxHeaders(request.headers)
         if isinstance(agent, self._TunnelingAgent):
@@ -214,7 +214,8 @@ class ScrapyAgent(object):
         bodyproducer = _RequestBodyProducer(request.body) if request.body else None
 
         start_time = time()
-        d = agent.request(method, url, headers, bodyproducer)
+        d = agent.request(
+            method, to_bytes(url, encoding='ascii'), headers, bodyproducer)
         # set download latency
         d.addCallback(self._cb_latency, request, start_time)
         # response body is ready to be consumed
@@ -267,10 +268,8 @@ class ScrapyAgent(object):
         txresponse, body, flags = result
         status = int(txresponse.code)
         headers = Headers(txresponse.headers.getAllRawHeaders())
-        url = to_unicode(url)
         respcls = responsetypes.from_args(headers=headers, url=url)
-        return respcls(
-            url=url, status=status, headers=headers, body=body, flags=flags)
+        return respcls(url=url, status=status, headers=headers, body=body, flags=flags)
 
 
 @implementer(IBodyProducer)