Send exit for flutter run --resident (#3829)

* send ext.flutter.exit

* listen for help restart, quit

* refactor into a separate class

packages/flutter_tools/lib/src/base/logger.dart

@@ -3,15 +3,16 @@
 // found in the LICENSE file.
 
 import 'dart:async';
+import 'dart:convert' show ASCII;
 import 'dart:io';
 
-final _AnsiTerminal _terminal = new _AnsiTerminal();
+final AnsiTerminal terminal = new AnsiTerminal();
 
 abstract class Logger {
   bool get isVerbose => false;
 
   set supportsColor(bool value) {
-    _terminal.supportsColor = value;
+    terminal.supportsColor = value;
   }
 
   /// Display an error level message to the user. Commands should use this if they
@@ -59,7 +60,7 @@ class StdoutLogger extends Logger {
     _status?.cancel();
     _status = null;
 
-    print(emphasis ? _terminal.writeBold(message) : message);
+    print(emphasis ? terminal.writeBold(message) : message);
   }
 
   @override
@@ -70,7 +71,7 @@ class StdoutLogger extends Logger {
     _status?.cancel();
     _status = null;
 
-    if (_terminal.supportsColor) {
+    if (terminal.supportsColor) {
       _status = new _AnsiStatus(message);
       return _status;
     } else {
@@ -177,34 +178,48 @@ class _LogMessage {
     String prefix = '${millis.toString().padLeft(4)} ms • ';
     String indent = ''.padLeft(prefix.length);
     if (millis >= 100)
-      prefix = _terminal.writeBold(prefix.substring(0, prefix.length - 3)) + ' • ';
+      prefix = terminal.writeBold(prefix.substring(0, prefix.length - 3)) + ' • ';
     String indentMessage = message.replaceAll('\n', '\n$indent');
 
     if (type == _LogType.error) {
-      stderr.writeln(prefix + _terminal.writeBold(indentMessage));
+      stderr.writeln(prefix + terminal.writeBold(indentMessage));
       if (stackTrace != null)
         stderr.writeln(indent + stackTrace.toString().replaceAll('\n', '\n$indent'));
     } else if (type == _LogType.status) {
-      print(prefix + _terminal.writeBold(indentMessage));
+      print(prefix + terminal.writeBold(indentMessage));
     } else {
       print(prefix + indentMessage);
     }
   }
 }
 
-class _AnsiTerminal {
-  _AnsiTerminal() {
+class AnsiTerminal {
+  AnsiTerminal() {
     // TODO(devoncarew): This detection does not work for Windows.
     String term = Platform.environment['TERM'];
     supportsColor = term != null && term != 'dumb';
   }
 
-  static const String _bold = '\u001B[1m';
+  static const String KEY_F1  = '\u001BOP';
+  static const String KEY_F5  = '\u001B[15~';
+  static const String KEY_F10 = '\u001B[21~';
+
+  static const String _bold  = '\u001B[1m';
   static const String _reset = '\u001B[0m';
 
   bool supportsColor;
 
   String writeBold(String str) => supportsColor ? '$_bold$str$_reset' : str;
+
+  set singleCharMode(bool value) {
+    stdin.echoMode = !value;
+    stdin.lineMode = !value;
+  }
+
+  /// Return keystrokes from the console.
+  ///
+  /// Useful when the console is in [singleCharMode].
+  Stream<String> get onCharInput => stdin.transform(ASCII.decoder);
 }
 
 class _AnsiStatus extends Status {

packages/flutter_tools/lib/src/commands/trace.dart

@@ -3,8 +3,8 @@
 // found in the LICENSE file.
 
 import 'dart:async';
-import 'dart:io';
 import 'dart:convert';
+import 'dart:io';
 
 import '../base/common.dart';
 import '../base/utils.dart';

packages/flutter_tools/lib/src/device.dart

@@ -12,8 +12,8 @@ import 'package:web_socket_channel/io.dart';
 import 'android/android_device.dart';
 import 'application_package.dart';
 import 'base/common.dart';
-import 'base/utils.dart';
 import 'base/os.dart';
+import 'base/utils.dart';
 import 'build_configuration.dart';
 import 'globals.dart';
 import 'ios/devices.dart';