Update to Chromium version 86.0.4240.0 (#800218)

- CefURLRequest::Create is no longer supported in the renderer process
  (see https://crbug.com/891872). Use CefFrame::CreateURLRequest instead.
- Mac platform definitions have been changed from `MACOSX` to `MAC`
  (see https://crbug.com/1105907) and related CMake macro names have
  been updated. The old `OS_MACOSX` define is still set in code and CMake
  for backwards compatibility.
- Linux ARM build is currently broken (see https://crbug.com/1123214).

tools/cef_api_hash.py

@@ -35,7 +35,7 @@ class cef_api_hash:
     self.__debug_enabled = not (self.__debugdir is
                                 None) and len(self.__debugdir) > 0
 
-    self.platforms = ["windows", "macosx", "linux"]
+    self.platforms = ["windows", "mac", "linux"]
 
     self.platform_files = {
         # List of includes_win_capi from cef_paths2.gypi.
@@ -43,7 +43,7 @@ class cef_api_hash:
             "internal/cef_types_win.h",
         ],
         # List of includes_mac_capi from cef_paths2.gypi.
-        "macosx": [
+        "mac": [
             "internal/cef_types_mac.h",
         ],
         # List of includes_linux_capi from cef_paths2.gypi.