Revert "#4965 fix: Accessing response.content twice removes forgets read error."

This reverts commit bd10047244.

This reverts commit d91fe00983.

tests/test_lowlevel.py

@@ -3,7 +3,6 @@
 import pytest
 import threading
 import requests
-from requests.exceptions import ChunkedEncodingError
 
 from tests.testserver.server import Server, consume_socket_content
 
@@ -308,43 +307,3 @@ def test_fragment_update_on_redirect():
         assert r.url == 'http://{}:{}/final-url/#relevant-section'.format(host, port)
 
         close_server.set()
-
-
-def test_response_content_retains_error():
-    """Verify that accessing response.content retains an error.
-
-    See https://github.com/kennethreitz/requests/issues/4965
-    """
-
-    data = "Some random stuff to read from remove server.\n"
-
-    def response_handler(sock):
-        req = consume_socket_content(sock, timeout=0.5)
-
-        # Send invalid chunked data (length mismatch)
-        sock.send(
-            b'HTTP/1.1 200 OK\r\n'
-            b'Transfer-Encoding: chunked\r\n'
-            b'\r\n2\r\n42\r\n8\r\n123\r\n'  # 5 bytes missing
-        )
-
-    close_server = threading.Event()
-    server = Server(response_handler, wait_to_close_event=close_server)
-
-    with server as (host, port):
-        url = 'http://{}:{}/path'.format(host, port)
-        r = requests.post(url, stream=True)
-        with pytest.raises(ChunkedEncodingError):
-            r.content
-
-    # Access the bad response data again, I would expect the same
-    # error again.
-
-    try:
-        content = r.content
-    except ChunkedEncodingError:
-        pass  # fine, same exception
-    else:
-        assert False, "error response has content: {0!r}".format(content)
-    close_server.set()
-