Remove old references to Node v4, small cleanup of node version stuff (#53174)

src/compiler/sys.ts

@@ -1449,21 +1449,6 @@ declare const global: any;
 declare const __filename: string;
 declare const __dirname: string;
 
-export function getNodeMajorVersion(): number | undefined {
-    if (typeof process === "undefined") {
-        return undefined;
-    }
-    const version: string = process.version;
-    if (!version) {
-        return undefined;
-    }
-    const dot = version.indexOf(".");
-    if (dot === -1) {
-        return undefined;
-    }
-    return parseInt(version.substring(1, dot));
-}
-
 // TODO: GH#18217 this is used as if it's certainly defined in many places.
 export let sys: System = (() => {
     // NodeJS detects "\uFEFF" at the start of the string and *replaces* it with the actual
@@ -1492,8 +1477,6 @@ export let sys: System = (() => {
             from?(input: string, encoding?: string): any;
         } = require("buffer").Buffer;
 
-        const nodeVersion = getNodeMajorVersion();
-        const isNode4OrLater = nodeVersion! >= 4;
         const isLinuxOrMacOs = process.platform === "linux" || process.platform === "darwin";
 
         const platform: string = _os.platform();
@@ -1507,7 +1490,7 @@ export let sys: System = (() => {
         // Note that if we ever emit as files like cjs/mjs, this check will be wrong.
         const executingFilePath = __filename.endsWith("sys.js") ? _path.join(_path.dirname(__dirname), "__fake__.js") : __filename;
 
-        const fsSupportsRecursiveFsWatch = isNode4OrLater && (process.platform === "win32" || process.platform === "darwin");
+        const fsSupportsRecursiveFsWatch = process.platform === "win32" || process.platform === "darwin";
         const getCurrentDirectory = memoize(() => process.cwd());
         const { watchFile, watchDirectory } = createSystemWatchFunctions({
             pollingWatchFileWorker: fsWatchFileWorker,