feat: netLog API for dynamic logging control (#13068)

* Introduce `net.{start|stop}Logging()`

- Slight regression right now as Electron won't automatically start logging net-logs at launch, will soon be fixed
- To implement callback for async controls

* Add `net.isLogging` & optional callback param for `net.stopLogging()`

* Fix small regression on --log-net-log

--log-net-log should work again

* Error on empty file path

* Only start with valid file path

* Remove unused var

* Allow setting log file path before URLRequestContextGetter starts logging

* Add net log tests

* Remove redundant checks

* Use brightray::NetLog

* Clean up code

* Should automatically stop listening

* 🎨 Attempt to fix styles

* Only run non-null callback

* Dump file to tmpdir

* Simplify net log spec

Spawned Electron process on Linux CI can fail to launch

* Separate netLog module

* Remove net logging test from net spec

* Add tests for netLog

* Fix header guard

* Clean up code

* Add netLog.currentlyLoggingPath

* Callback with filepath

* Add test for case when only .stopLogging() is called

* Add docs

* Reintroduce error on invalid arg

* Update copyright

* Update error message

* Juggle file path string types

spec/fixtures/api/net-log/main.js

@@ -0,0 +1,33 @@
+const {app, net, netLog} = require('electron')
+
+function request () {
+  return new Promise((resolve) => {
+    const req = net.request(process.env.TEST_REQUEST_URL)
+    req.on('response', () => {
+      resolve()
+    })
+    req.end()
+  })
+}
+
+function stopLogging () {
+  return new Promise((resolve) => {
+    netLog.stopLogging(() => {
+      resolve()
+    })
+  })
+}
+
+app.on('ready', async () => {
+  if (process.env.TEST_DUMP_FILE) {
+    netLog.startLogging(process.env.TEST_DUMP_FILE)
+  }
+
+  await request()
+
+  if (process.env.TEST_MANUAL_STOP) {
+    await stopLogging()
+  }
+
+  app.quit()
+})