http2: remove some unnecessary next ticks

Backport-PR-URL: #20456
PR-URL: #19451
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

lib/internal/http2/core.js

@@ -361,7 +361,7 @@ function onSettings() {
   session[kUpdateTimer]();
   debug(`Http2Session ${sessionName(session[kType])}: new settings received`);
   session[kRemoteSettings] = undefined;
-  process.nextTick(emit, session, 'remoteSettings', session.remoteSettings);
+  session.emit('remoteSettings', session.remoteSettings);
 }
 
 // If the stream exists, an attempt will be made to emit an event
@@ -377,7 +377,7 @@ function onPriority(id, parent, weight, exclusive) {
   const emitter = session[kState].streams.get(id) || session;
   if (!emitter.destroyed) {
     emitter[kUpdateTimer]();
-    process.nextTick(emit, emitter, 'priority', id, parent, weight, exclusive);
+    emitter.emit('priority', id, parent, weight, exclusive);
   }
 }
 
@@ -391,7 +391,7 @@ function onFrameError(id, type, code) {
         `type ${type} on stream ${id}, code: ${code}`);
   const emitter = session[kState].streams.get(id) || session;
   emitter[kUpdateTimer]();
-  process.nextTick(emit, emitter, 'frameError', type, code, id);
+  emitter.emit('frameError', type, code, id);
 }
 
 function onAltSvc(stream, origin, alt) {
@@ -401,7 +401,7 @@ function onAltSvc(stream, origin, alt) {
   debug(`Http2Session ${sessionName(session[kType])}: altsvc received: ` +
         `stream: ${stream}, origin: ${origin}, alt: ${alt}`);
   session[kUpdateTimer]();
-  process.nextTick(emit, session, 'altsvc', alt, origin, stream);
+  session.emit('altsvc', alt, origin, stream);
 }
 
 // Receiving a GOAWAY frame from the connected peer is a signal that no
@@ -731,7 +731,7 @@ function setupHandle(socket, type, options) {
   // core will check for session.destroyed before progressing, this
   // ensures that those at l`east get cleared out.
   if (this.destroyed) {
-    process.nextTick(emit, this, 'connect', this, socket);
+    this.emit('connect', this, socket);
     return;
   }
   debug(`Http2Session ${sessionName(type)}: setting up session handle`);
@@ -773,7 +773,7 @@ function setupHandle(socket, type, options) {
     options.settings : {};
 
   this.settings(settings);
-  process.nextTick(emit, this, 'connect', this, socket);
+  this.emit('connect', this, socket);
 }
 
 // Emits a close event followed by an error event if err is truthy. Used
@@ -1224,7 +1224,7 @@ class Http2Session extends EventEmitter {
       }
     }
 
-    process.nextTick(emit, this, 'timeout');
+    this.emit('timeout');
   }
 
   ref() {
@@ -1452,8 +1452,8 @@ function streamOnPause() {
 function abort(stream) {
   if (!stream.aborted &&
       !(stream._writableState.ended || stream._writableState.ending)) {
-    process.nextTick(emit, stream, 'aborted');
     stream[kState].flags |= STREAM_FLAGS_ABORTED;
+    stream.emit('aborted');
   }
 }
 
@@ -1575,7 +1575,7 @@ class Http2Stream extends Duplex {
       }
     }
 
-    process.nextTick(emit, this, 'timeout');
+    this.emit('timeout');
   }
 
   // true if the HEADERS frame has been sent