merge from 3.4

Fix Issue #8797: Raise HTTPError on failed Basic Authentication immediately. Initial patch by Sam Bull.

diff --cc Misc/NEWS
index 9e2b198ac30c555f09e65ddd6163afdfcd3ae5c2,9c4f5606a3d4626fea66178eabe8b5e6d2979ac1..ed7865ef8b6cbca3e1061bcfac06603ce838464e
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -130,8 -33,9 +130,11 @@@ Librar
  
  - Issue #22165: SimpleHTTPRequestHandler now supports undecodable file names.
  
 +- Issue #15381: Optimized line reading in io.BytesIO.
 +
+ - Issue #8797: Raise HTTPError on failed Basic Authentication immediately.
+   Initial patch by Sam Bull.
+ 
  - Issue #20729: Restored the use of lazy iterkeys()/itervalues()/iteritems()
    in the mailbox module.