pw_web_ui: Add `baudRate` in additon to `baudrate` to serial options

On some versions of Chrome (such as on Chromebooks), the options used to
open a serial port use `baudRate` instead of `baudrate` to indicate the
baud rate of the connection. This CL adds `baudRate` to the default
options.

Change-Id: I7146d551210d41bf31ed53b842e59dae44127920
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/18685
Reviewed-by: Paul Mathieu <paulmathieu@google.com>
Pigweed-Auto-Submit: Matthew Soulanille <msoulanille@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/pw_web_ui/src/transport/web_serial_transport.ts b/pw_web_ui/src/transport/web_serial_transport.ts
index fca0a71..7a95379 100644
--- a/pw_web_ui/src/transport/web_serial_transport.ts
+++ b/pw_web_ui/src/transport/web_serial_transport.ts
@@ -16,8 +16,11 @@
 import {BehaviorSubject, Subject, Subscription, Observable} from 'rxjs';
 import DeviceTransport from './device_transport';
 
-const DEFAULT_SERIAL_OPTIONS: SerialOptions = {
+const DEFAULT_SERIAL_OPTIONS: SerialOptions & {baudRate: number} = {
+  // Some versions of chrome use `baudrate` (linux)
   baudrate: 921600,
+  // Some versions use `baudRate` (chromebook)
+  baudRate: 921600,
   databits: 8,
   parity: 'none',
   stopbits: 1,