Remove redundant lines from errors

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

@@ -45,8 +45,6 @@ class AndroidEmulator extends Emulator {
     final RunResult launchResult =
         await runAsync(<String>[getEmulatorPath(), '-avd', id]);
     if (launchResult.exitCode != 0) {
-      printError(
-          'Error: emulator exited with exit code ${launchResult.exitCode}');
       printError('$launchResult');
       return false;
     }

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

@@ -41,8 +41,6 @@ class IOSEmulator extends Emulator {
     final RunResult launchResult =
         await runAsync(<String>['open', '-a', getSimulatorPath()]);
     if (launchResult.exitCode != 0) {
-      printError(
-          'Error: iOS simulator failed to launch with exit code ${launchResult.exitCode}');
       printError('$launchResult');
       return false;
     }