Fix third_party errors with --disallow-any-generics (#3278)

Part of #3267. Together with #3276 this should fix all such problems.

third_party/2/gflags.pyi

@@ -35,7 +35,7 @@ class FlagValues:
     def is_gnu_getopt(self) -> bool: ...
     IsGnuGetOpt = is_gnu_getopt
     # TODO dict type
-    def FlagDict(self) -> dict: ...
+    def FlagDict(self) -> Dict[Any, Any]: ...
     def flags_by_module_dict(self) -> Dict[str, List[Flag]]: ...
     FlagsByModuleDict = flags_by_module_dict
     def flags_by_module_id_dict(self) -> Dict[int, List[Flag]]: ...
@@ -206,7 +206,7 @@ def DEFINE_enum(name: str, default: Optional[str], enum_values: List[str], help:
 
 class BaseListParser(ArgumentParser):
     def __init__(self, token: str = ..., name: str = ...) -> None: ...
-    def Parse(self, argument: Any) -> list: ...
+    def Parse(self, argument: Any) -> List[Any]: ...
 
 class ListParser(BaseListParser):
     def __init__(self) -> None: ...

third_party/2/tornado/httputil.pyi

@@ -1,16 +1,16 @@
-from typing import Any
+from typing import Any, Dict
 from tornado.util import ObjectDict
 from collections import namedtuple
 
 class SSLError(Exception): ...
 
-class _NormalizedHeaderCache(dict):
+class _NormalizedHeaderCache(Dict[Any, Any]):
     size: Any
     queue: Any
     def __init__(self, size) -> None: ...
     def __missing__(self, key): ...
 
-class HTTPHeaders(dict):
+class HTTPHeaders(Dict[Any, Any]):
     def __init__(self, *args, **kwargs) -> None: ...
     def add(self, name, value): ...
     def get_list(self, name): ...

third_party/2/tornado/testing.pyi

@@ -43,12 +43,9 @@ class AsyncHTTPSTestCase(AsyncHTTPTestCase):
     def get_protocol(self): ...
 
 @overload
-def gen_test(*, timeout: Optional[float] = ...) -> Callable[[Callable[..., Generator]], Callable[..., None]]:
-    ...
-
+def gen_test(*, timeout: Optional[float] = ...) -> Callable[[Callable[..., Generator[Any, Any, Any]]], Callable[..., None]]: ...
 @overload
-def gen_test(func: Callable[..., Generator]) -> Callable[..., None]:
-    ...
+def gen_test(func: Callable[..., Generator[Any, Any, Any]]) -> Callable[..., None]: ...
 
 class LogTrapTestCase(unittest.TestCase):
     def run(self, result: Optional[Any] = ...): ...

third_party/2/tornado/util.pyi

@@ -1,8 +1,8 @@
-from typing import Any
+from typing import Any, Dict
 
 xrange: Any
 
-class ObjectDict(dict):
+class ObjectDict(Dict[Any, Any]):
     def __getattr__(self, name): ...
     def __setattr__(self, name, value): ...