Specify UDID for idevicelistener. (#23854)

This is needed to run flutter app on multiple iOS devices at a time.

packages/flutter_tools/lib/src/ios/devices.dart

@@ -475,7 +475,7 @@ class _IOSDeviceLogReader extends DeviceLogReader {
   String get name => device.name;
 
   void _start() {
-    iMobileDevice.startLogger().then<void>((Process process) {
+    iMobileDevice.startLogger(device.id).then<void>((Process process) {
       _process = process;
       _process.stdout.transform<String>(utf8.decoder).transform<String>(const LineSplitter()).listen(_newLineHandler());
       _process.stderr.transform<String>(utf8.decoder).transform<String>(const LineSplitter()).listen(_newLineHandler());

packages/flutter_tools/lib/src/ios/mac.dart

@@ -127,7 +127,7 @@ class IMobileDevice {
   }
 
   /// Starts `idevicesyslog` and returns the running process.
-  Future<Process> startLogger() => runCommand(<String>['idevicesyslog']);
+  Future<Process> startLogger(String deviceID) => runCommand(<String>['idevicesyslog', '-u', deviceID]);
 
   /// Captures a screenshot to the specified outputFile.
   Future<void> takeScreenshot(File outputFile) {

packages/flutter_tools/test/ios/devices_test.dart

@@ -100,7 +100,7 @@ f577a7903cc54959be2e34bc4f7f80b7009efcf4
     });
 
     testUsingContext('suppresses non-Flutter lines from output', () async {
-      when(mockIMobileDevice.startLogger()).thenAnswer((Invocation invocation) {
+      when(mockIMobileDevice.startLogger('123456')).thenAnswer((Invocation invocation) {
         final Process mockProcess = MockProcess();
         when(mockProcess.stdout).thenAnswer((Invocation invocation) =>
             Stream<List<int>>.fromIterable(<List<int>>['''
@@ -130,7 +130,7 @@ f577a7903cc54959be2e34bc4f7f80b7009efcf4
     });
 
     testUsingContext('includes multi-line Flutter logs in the output', () async {
-      when(mockIMobileDevice.startLogger()).thenAnswer((Invocation invocation) {
+      when(mockIMobileDevice.startLogger('123456')).thenAnswer((Invocation invocation) {
         final Process mockProcess = MockProcess();
         when(mockProcess.stdout).thenAnswer((Invocation invocation) =>
             Stream<List<int>>.fromIterable(<List<int>>['''