Suppress Scanner advertisement delivery failures (#68)

When `callbackFlow`'s `Channel` is closed due to downstream `Flow` being
cancelled then sending to the `Channel` can unexpectedly throw an
exception. We suppress the exception, as it is assumed that `Flow` is
shutting down anyways.

Author: twyatt

core/src/androidMain/kotlin/Scanner.kt

@@ -3,6 +3,7 @@ package com.juul.kable
 import android.bluetooth.BluetoothAdapter
 import android.bluetooth.le.ScanCallback
 import android.bluetooth.le.ScanResult
+import android.util.Log
 import kotlinx.coroutines.cancel
 import kotlinx.coroutines.channels.awaitClose
 import kotlinx.coroutines.channels.sendBlocking
@@ -25,12 +26,20 @@ public class AndroidScanner internal constructor() : Scanner {
 
         val callback = object : ScanCallback() {
             override fun onScanResult(callbackType: Int, result: ScanResult) {
-                sendBlocking(Advertisement(result))
+                runCatching {
+                    sendBlocking(Advertisement(result))
+                }.onFailure {
+                    Log.w(TAG, "Unable to deliver scan result due to failure in flow or premature closing.")
+                }
             }
 
             override fun onBatchScanResults(results: MutableList<ScanResult>) {
-                results.forEach {
-                    sendBlocking(Advertisement(it))
+                runCatching {
+                    results.forEach {
+                        sendBlocking(Advertisement(it))
+                    }
+                }.onFailure {
+                    Log.w(TAG, "Unable to deliver batch scan results due to failure in flow or premature closing.")
                 }
             }
 

core/src/jsMain/kotlin/Scanner.kt

@@ -31,7 +31,11 @@ public class JsScanner internal constructor(
 
         val scan = bluetooth.requestLEScan(options.toDynamic()).await()
         val listener: (Event) -> Unit = {
-            offer(Advertisement(it as BluetoothAdvertisingEvent))
+            runCatching {
+                offer(Advertisement(it as BluetoothAdvertisingEvent))
+            }.onFailure {
+                console.warn("Unable to deliver advertisement event due to failure in flow or premature closing.")
+            }
         }
         bluetooth.addEventListener(ADVERTISEMENT_RECEIVED_EVENT, listener)