Remove Python 3.4 support (#3147)

Closes #3123

stdlib/3/html/parser.pyi

@@ -3,11 +3,7 @@ from _markupbase import ParserBase
 import sys
 
 class HTMLParser(ParserBase):
-    if sys.version_info >= (3, 5):
-        def __init__(self, *, convert_charrefs: bool = ...) -> None: ...
-    else:
-        def __init__(self, strict: bool = ..., *,
-                     convert_charrefs: bool = ...) -> None: ...
+    def __init__(self, *, convert_charrefs: bool = ...) -> None: ...
     def feed(self, feed: str) -> None: ...
     def close(self) -> None: ...
     def reset(self) -> None: ...
@@ -26,6 +22,3 @@ class HTMLParser(ParserBase):
     def handle_decl(self, decl: str) -> None: ...
     def handle_pi(self, data: str) -> None: ...
     def unknown_decl(self, data: str) -> None: ...
-
-if sys.version_info < (3, 5):
-    class HTMLParseError(Exception): ...