inspector: convert to buffer in inspector instead of http2 core

Signed-off-by: Darshan Sen <raisinten@gmail.com>

Author: RaisinTen

lib/internal/inspector/network_http2.js

@@ -29,6 +29,7 @@ const {
   NGHTTP2_NO_ERROR,
 } = internalBinding('http2').constants;
 const EventEmitter = require('events');
+const { Buffer } = require('buffer');
 
 const kRequestUrl = Symbol('kRequestUrl');
 
@@ -126,13 +127,40 @@ function onClientStreamError({ stream, error }) {
 /**
  * When a chunk of the request body is being sent, cache it until `getRequestPostData` request.
  * https://chromedevtools.github.io/devtools-protocol/1-3/Network/#method-getRequestPostData
- * @param {{ stream: import('http2').ClientHttp2Stream, chunk: Buffer }} event
+ * @param {{
+ *   stream: import('http2').ClientHttp2Stream,
+ *   writev: boolean,
+ *   data: Buffer | string | Array<Buffer | {chunk: Buffer|string, encoding: string}>,
+ *   encoding: string,
+ * }} event
  */
-function onClientStreamBodyChunkSent({ stream, chunk }) {
+function onClientStreamBodyChunkSent({ stream, writev, data, encoding }) {
   if (typeof stream[kInspectorRequestId] !== 'string') {
     return;
   }
 
+  let chunk;
+
+  if (writev) {
+    if (data.allBuffers) {
+      chunk = Buffer.concat(data);
+    } else {
+      const buffers = [];
+      for (let i = 0; i < data.length; ++i) {
+        if (typeof data[i].chunk === 'string') {
+          buffers.push(Buffer.from(data[i].chunk, data[i].encoding));
+        } else {
+          buffers.push(data[i].chunk);
+        }
+      }
+      chunk = Buffer.concat(buffers);
+    }
+  } else if (typeof data === 'string') {
+    chunk = Buffer.from(data, encoding);
+  } else {
+    chunk = data;
+  }
+
   Network.dataSent({
     requestId: stream[kInspectorRequestId],
     timestamp: getMonotonicTime(),