style fixes (#6662)

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

@@ -45,7 +45,7 @@ class RunCommand extends RunCommandBase {
   @override
   final String description = 'Run your Flutter app on an attached device.';
 
-  RunCommand({bool verboseHelp: false}) {
+  RunCommand({ bool verboseHelp: false }) {
     argParser.addFlag('full-restart',
         defaultsTo: true,
         help: 'Stop any currently running application process before running the app.');
@@ -64,16 +64,20 @@ class RunCommand extends RunCommandBase {
     usesPubOption();
 
     // Option to enable hot reloading.
-    argParser.addFlag('hot',
+    argParser.addFlag(
+      'hot',
       negatable: true,
       defaultsTo: kHotReloadDefault,
-                      help: 'Run with support for hot reloading.');
+      help: 'Run with support for hot reloading.'
+    );
 
     // Option to write the pid to a file.
-    argParser.addOption('pid-file',
-                        help: "Specify a file to write the process id to.\n"
-                              "You can send SIGUSR1 to trigger a hot reload\n"
-                              "and SIGUSR2 to trigger a full restart.");
+    argParser.addOption(
+      'pid-file',
+      help: 'Specify a file to write the process id to.\n'
+            'You can send SIGUSR1 to trigger a hot reload\n'
+            'and SIGUSR2 to trigger a full restart.'
+    );
 
 
     // Hidden option to enable a benchmarking mode. This will run the given
@@ -273,7 +277,7 @@ Future<int> startApp(
   // messy.
   if (stop) {
     if (package != null) {
-      printTrace("Stopping app '${package.name}' on ${device.name}.");
+      printTrace('Stopping app "${package.name}" on ${device.name}.');
       await device.stopApp(package);
     }
   }

packages/flutter_tools/lib/src/run.dart

@@ -144,7 +144,7 @@ class RunAndStayResident extends ResidentRunner {
 
     // TODO(devoncarew): Move this into the device.startApp() impls.
     if (_package != null) {
-      printTrace("Stopping app '${_package.name}' on ${device.name}.");
+      printTrace('Stopping app "${_package.name}" on ${device.name}.');
       await device.stopApp(_package);
     }