tests: fix style issue of importing hgweb in embedded code fragments

tests: fix style issue of importing hgweb in embedded code fragments

Some test scripts are excluded in test-check-module-imports.t, because
import-checker.py reports that hgweb and/or hgwebdir of
mercurial.hgweb are not imported in recommended style.

To fix this issues, this patch make python code fragments embedded in
these files import hgweb from mercurial package at first, and refer
hgweb and hgwebdir via imported hgweb.

--- a/tests/test-hgweb-no-path-info.t	Fri Oct 12 18:20:17 2018 +0200
+++ b/tests/test-hgweb-no-path-info.t	Mon Oct 08 10:10:06 2018 +0900
@@ -18,11 +18,8 @@
   > from __future__ import absolute_import
   > import os
   > import sys
-  > from mercurial.hgweb import (
+  > from mercurial import (
   >     hgweb,
-  >     hgwebdir,
-  > )
-  > from mercurial import (
   >     util,
   > )
   > stringio = util.stringio
@@ -72,11 +69,11 @@
   > 
   > output = stringio()
   > env['QUERY_STRING'] = 'style=atom'
-  > process(hgweb(b'.', name=b'repo'))
+  > process(hgweb.hgweb(b'.', name=b'repo'))
   > 
   > output = stringio()
   > env['QUERY_STRING'] = 'style=raw'
-  > process(hgwebdir({b'repo': b'.'}))
+  > process(hgweb.hgwebdir({b'repo': b'.'}))
   > EOF
   $ "$PYTHON" request.py
   ---- STATUS

--- a/tests/test-hgweb-no-request-uri.t	Fri Oct 12 18:20:17 2018 +0200
+++ b/tests/test-hgweb-no-request-uri.t	Mon Oct 08 10:10:06 2018 +0900
@@ -18,12 +18,9 @@
   > from __future__ import absolute_import
   > import os
   > import sys
-  > from mercurial.hgweb import (
-  >     hgweb,
-  >     hgwebdir,
-  > )
   > from mercurial import (
   >     encoding,
+  >     hgweb,
   >     util,
   > )
   > stringio = util.stringio
@@ -65,22 +62,22 @@
   > output = stringio()
   > env['PATH_INFO'] = '/'
   > env['QUERY_STRING'] = 'style=atom'
-  > process(hgweb(b'.', name = b'repo'))
+  > process(hgweb.hgweb(b'.', name = b'repo'))
   > 
   > output = stringio()
   > env['PATH_INFO'] = '/file/tip/'
   > env['QUERY_STRING'] = 'style=raw'
-  > process(hgweb(b'.', name = b'repo'))
+  > process(hgweb.hgweb(b'.', name = b'repo'))
   > 
   > output = stringio()
   > env['PATH_INFO'] = '/'
   > env['QUERY_STRING'] = 'style=raw'
-  > process(hgwebdir({b'repo': b'.'}))
+  > process(hgweb.hgwebdir({b'repo': b'.'}))
   > 
   > output = stringio()
   > env['PATH_INFO'] = '/repo/file/tip/'
   > env['QUERY_STRING'] = 'style=raw'
-  > process(hgwebdir({b'repo': b'.'}))
+  > process(hgweb.hgwebdir({b'repo': b'.'}))
   > EOF
   $ "$PYTHON" request.py
   ---- STATUS

--- a/tests/test-hgweb-non-interactive.t	Fri Oct 12 18:20:17 2018 +0200
+++ b/tests/test-hgweb-non-interactive.t	Mon Oct 08 10:10:06 2018 +0900
@@ -19,9 +19,7 @@
   >     util,
   > )
   > ui = uimod.ui
-  > from mercurial.hgweb.hgweb_mod import (
-  >     hgweb,
-  > )
+  > from mercurial.hgweb import hgweb_mod
   > stringio = util.stringio
   > 
   > class FileLike(object):
@@ -67,7 +65,7 @@
   >     'SERVER_PROTOCOL': 'HTTP/1.0'
   > }
   > 
-  > i = hgweb(b'.')
+  > i = hgweb_mod.hgweb(b'.')
   > for c in i(env, startrsp):
   >     pass
   > sys.stdout.flush()