Call process.stdout._handle.setBlocking(true) (#22389)

* Call process.stdout._handle.setBlocking(true)

This prevents output from being truncated when the compiler can output
errors to stdout faster than it can receive them. This may slow down
performance for compilations for many errors, but those were already
quite slow.

* Disable tslint no-unnnecessary-type-assertion-2

It is wrong. It *is* necessary.

src/compiler/tsc.ts

@@ -399,4 +399,8 @@ if (ts.Debug.isDebugging) {
 if (ts.sys.tryEnableSourceMapsForHost && /^development$/i.test(ts.sys.getEnvironmentVariable("NODE_ENV"))) {
     ts.sys.tryEnableSourceMapsForHost();
 }
+declare var process: any;
+if (process && process.stdout && process.stdout._handle && process.stdout._handle.setBlocking) {
+    process.stdout._handle.setBlocking(true);
+}
 ts.executeCommandLine(ts.sys.args);

src/server/server.ts

@@ -991,6 +991,7 @@ namespace ts.server {
         ioSession.logError(err, "unknown");
     });
     // See https://github.com/Microsoft/TypeScript/issues/11348
+    // tslint:disable-next-line no-unnecessary-type-assertion-2
     (process as any).noAsar = true;
     // Start listening
     ioSession.listen();