license and doc: Add support for python3

With homebrew's recent change of making python3 the default
over python2, lets support python3.

Bug: Issue 8474
Change-Id: I8dba441c8d717ae06d156c9201a02926884fd5f0

Documentation/replace_macros.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python
 # coding=utf-8
 # Copyright (C) 2013 The Android Open Source Project
 #
@@ -229,12 +229,16 @@ opts.add_option('--no-searchbox', action="store_false", dest='searchbox',
 options, _ = opts.parse_args()
 
 try:
+  try:
+    out_file = open(options.out, 'w', errors='ignore')
+    src_file = open(options.src, 'r', errors='ignore')
+  except TypeError:
     out_file = open(options.out, 'w')
     src_file = open(options.src, 'r')
   last_line = ''
   ignore_next_line = False
   last_title = ''
-  for line in src_file.xreadlines():
+  for line in src_file:
     if PAT_GERRIT.match(last_line):
       # Case of "GERRIT\n------" at the footer
       out_file.write(GERRIT_UPLINK)

tools/bzl/license-map.py

@@ -113,7 +113,12 @@ for n in sorted(graph.keys()):
   print()
   print("[[%s_license]]" % safename)
   print("----")
-  with open(n[2:].replace(":", "/")) as fd:
+  filename = n[2:].replace(":", "/")
+  try:
+    with open(filename, errors='ignore') as fd:
+      copyfileobj(fd, stdout)
+  except TypeError:
+    with open(filename) as fd:
       copyfileobj(fd, stdout)
   print()
   print("----")

tools/bzl/license.bzl

@@ -25,7 +25,7 @@ def license_map(name, targets = [], opts = [], **kwargs):
   # post process the XML into our favorite format.
   native.genrule(
     name = "gen_license_txt_" + name,
-    cmd = "python2 $(location //tools/bzl:license-map.py) %s %s > $@" % (" ".join(opts), " ".join(xmls)),
+    cmd = "python $(location //tools/bzl:license-map.py) %s %s > $@" % (" ".join(opts), " ".join(xmls)),
     outs = [ name + ".txt" ],
     tools = tools,
     **kwargs