mypy: Added Dict, List and Set imports.

Fixed mypy errors associated with the upgrade.

tools/create-test-api-docs

@@ -7,7 +7,7 @@ from lib import sanity_check
 sanity_check.check_venv(__file__)
 
 from collections import defaultdict
-from typing import Any, Dict, Iterable, Set
+from typing import Any, Dict, Iterable, List, Set
 
 import cgi
 import os

tools/html-grep

@@ -6,6 +6,7 @@ import optparse
 import sys
 
 from six.moves import filter
+from typing import List
 
 # check for the venv
 from lib import sanity_check

tools/lib/find_add_class.py

@@ -1,7 +1,7 @@
 from __future__ import absolute_import
 from __future__ import print_function
 
-from typing import Set, Tuple
+from typing import List, Set, Tuple
 
 import os
 import re

tools/lib/html_branches.py

@@ -1,7 +1,7 @@
 from __future__ import absolute_import
 from __future__ import print_function
 
-from typing import Optional
+from typing import Dict, List, Optional, Set
 
 import re
 from collections import defaultdict

tools/lib/html_grep.py

@@ -2,6 +2,7 @@ from __future__ import absolute_import
 from __future__ import print_function
 from collections import defaultdict
 from six.moves import range
+from typing import Dict, List, Set
 
 from .html_branches import html_branches, HtmlTreeBranch
 

tools/lib/pretty_print.py

@@ -1,7 +1,7 @@
 from __future__ import absolute_import
 from __future__ import print_function
 
-from typing import Any
+from typing import Any, Dict, List
 
 from .template_parser import (
     tokenize,

tools/lib/template_parser.py

@@ -1,6 +1,6 @@
 from __future__ import absolute_import
 from __future__ import print_function
-from typing import Callable, Optional
+from typing import Callable, List, Optional
 from six.moves import range
 import re
 

tools/run-dev.py

@@ -25,7 +25,7 @@ from tornado.ioloop import IOLoop
 from tornado.websocket import WebSocketHandler, websocket_connect
 
 if False:
-    from typing import Any, Callable, Generator, Optional
+    from typing import Any, Callable, Generator, List, Optional
 
 if 'posix' in os.name and os.geteuid() == 0:
     raise RuntimeError("run-dev.py should not be run as root.")

tools/setup/emoji/build_emoji

@@ -12,7 +12,7 @@ import sys
 import hashlib
 import xml.etree.ElementTree as ET
 from six import unichr
-from typing import Union, Text
+from typing import Dict, Text, Union
 from os.path import dirname
 from PIL import Image, ImageDraw, ImageFont
 

tools/setup/emoji/emoji_setup_utils.py

@@ -13,7 +13,7 @@ from itertools import permutations, chain
 import ujson
 
 from six.moves import range, zip
-from typing import Text
+from typing import Dict, List, Text
 
 # the corresponding code point will be set to exactly these names as a
 # final pass, overriding any other rules.  This is useful for cases

tools/test_user_agent_parsing.py

@@ -4,6 +4,7 @@ import re
 from collections import defaultdict
 import os
 import sys
+from typing import Dict
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))