Revert "src: make process.env.TZ setter clear tz cache"

This reverts commit 1d1ab76.

PR-URL: #20228
Fixes: #20227
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/node.cc

@@ -80,7 +80,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
-#include <time.h>  // tzset(), _tzset()
 
 #include <string>
 #include <vector>
@@ -136,7 +135,6 @@ using v8::Array;
 using v8::ArrayBuffer;
 using v8::Boolean;
 using v8::Context;
-using v8::Date;
 using v8::EscapableHandleScope;
 using v8::Exception;
 using v8::Float64Array;
@@ -2690,10 +2688,6 @@ static void EnvSetter(Local<Name> property,
   node::Utf8Value key(info.GetIsolate(), property);
   node::Utf8Value val(info.GetIsolate(), value);
   setenv(*key, *val, 1);
-  if (key.length() == 2 && key[0] == 'T' && key[1] == 'Z') {
-    tzset();
-    Date::DateTimeConfigurationChangeNotification(info.GetIsolate());
-  }
 #else  // _WIN32
   node::TwoByteValue key(info.GetIsolate(), property);
   node::TwoByteValue val(info.GetIsolate(), value);
@@ -2702,10 +2696,6 @@ static void EnvSetter(Local<Name> property,
   if (key_ptr[0] != L'=') {
     SetEnvironmentVariableW(key_ptr, reinterpret_cast<WCHAR*>(*val));
   }
-  if (key.length() == 2 && key[0] == L'T' && key[1] == L'Z') {
-    _tzset();
-    Date::DateTimeConfigurationChangeNotification(info.GetIsolate());
-  }
 #endif
   // Whether it worked or not, always return value.
   info.GetReturnValue().Set(value);