repopick: support auth'ing to gerrit and picking drafts

* Use requests if installed. If not fall back to urllib. This is
  done because users may or may not have requests installed and
  requiring them to do so for simple http stuff isn't really
  reasonable.

* If requests is installed and a .gerritrc file exists in the
  user's HOME directory, try to get credentials out of it
  for the given gerrit instance. If auth for the correct gerrit
  instance exists, use it to auth to gerrit. If no .gerritrc
  exists, just use requests with no auth.

  Example ~/.gerritrc entry:
  review.lineageos.org|invisiblek|httppasswordhere

Change-Id: I95be26d51bfd31b53f3613e8dbfb7bba46324571

build/tools/repopick.py

@@ -31,6 +31,9 @@ import argparse
 import textwrap
 from xml.etree import ElementTree
 
+try:
+    import requests
+except ImportError:
     try:
         # For python3
         import urllib.error
@@ -100,7 +103,25 @@ def fetch_query_via_ssh(remote_url, query):
 
 
 def fetch_query_via_http(remote_url, query):
-
+    if "requests" in sys.modules:
+        auth = None
+        if os.path.isfile(os.getenv("HOME") + "/.gerritrc"):
+            f = open(os.getenv("HOME") + "/.gerritrc", "r")
+            for line in f:
+                parts = line.rstrip().split("|")
+                if parts[0] in remote_url:
+                    auth = requests.auth.HTTPBasicAuth(username=parts[1], password=parts[2])
+        statusCode = '-1'
+        if auth:
+            url = '{0}/a/changes/?q={1}&o=CURRENT_REVISION&o=ALL_REVISIONS'.format(remote_url, query)
+            data = requests.get(url, auth=auth)
+            statusCode = str(data.status_code)
+        if statusCode != '200':
+            #They didn't get good authorization or data, Let's try the old way
+            url = '{0}/changes/?q={1}&o=CURRENT_REVISION&o=ALL_REVISIONS'.format(remote_url, query)
+            data = requests.get(url)
+        reviews = json.loads(data.text[5:])
+    else:
         """Given a query, fetch the change numbers via http"""
         url = '{0}/changes/?q={1}&o=CURRENT_REVISION&o=ALL_REVISIONS'.format(remote_url, query)
         data = urllib.request.urlopen(url).read().decode('utf-8')