Add missing awaits

packages/flutter_tools/lib/src/android/android_emulator.dart

@@ -41,15 +41,13 @@ class AndroidEmulator extends Emulator {
   String get label => _properties['avd.ini.displayname'];
 
   @override
-  Future<bool> launch() async {
+  Future<void> launch() async {
     final RunResult launchResult =
         await runAsync(<String>[getEmulatorPath(), '-avd', id]);
+
     if (launchResult.exitCode != 0) {
       printError('$launchResult');
-      return false;
     }
-
-    return true;
   }
 }
 

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

@@ -55,7 +55,7 @@ class EmulatorsCommand extends FlutterCommand {
       printStatus("More than one emulator matches '$id':\n");
       Emulator.printEmulators(emulators);
     } else {
-      emulators.first.launch();
+      await emulators.first.launch();
     }
   }
 

packages/flutter_tools/lib/src/emulator.dart

@@ -95,7 +95,7 @@ abstract class Emulator {
     return id == other.id;
   }
 
-  void launch();
+  Future<void> launch();
 
   @override
   String toString() => name;

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

@@ -35,15 +35,12 @@ class IOSEmulator extends Emulator {
   String get label => null;
 
   @override
-  Future<bool> launch() async {
+  Future<void> launch() async {
     final RunResult launchResult =
         await runAsync(<String>['open', '-a', getSimulatorPath()]);
     if (launchResult.exitCode != 0) {
       printError('$launchResult');
-      return false;
     }
-
-    return true;
   }
 }