Auto merge of #14276 - szeged:notify, r=jdm

Add Start/Stop notifications

Add support for Start and Stop Notifications for WebBluetooth

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] There are tests for these changes

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components/bluetooth_traits/lib.rs

@@ -92,6 +92,7 @@ pub enum BluetoothRequest {
     GetDescriptors(String, Option<String>, IpcSender<BluetoothResponseResult>),
     ReadValue(String, IpcSender<BluetoothResponseResult>),
     WriteValue(String, Vec<u8>, IpcSender<BluetoothResponseResult>),
+    EnableNotification(String, bool, IpcSender<BluetoothResponseResult>),
     Test(String, IpcSender<BluetoothResult<()>>),
     Exit,
 }
@@ -110,6 +111,7 @@ pub enum BluetoothResponse {
     GetDescriptors(BluetoothDescriptorsMsg),
     ReadValue(Vec<u8>),
     WriteValue(Vec<u8>),
+    EnableNotification(()),
 }
 
 pub trait BluetoothResponseListener {