fix spacing issue and add test for supportsHardwareRendering (#15305)

* fix spacing issue and add test for supportsHardwareRendering

* remove extra async tag

* move spacing to prev line

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

@@ -289,12 +289,12 @@ class RunCommand extends RunCommandBase {
           final bool enableSoftwareRendering = argResults['enable-software-rendering'] == true;
           if (enableSoftwareRendering) {
             printStatus(
-              'Using software rendering with device ${device.name}. You may get better performance'
+              'Using software rendering with device ${device.name}. You may get better performance '
               'with hardware mode by configuring hardware rendering for your device.'
             );
           } else {
             printStatus(
-              'Using hardware rendering with device ${device.name}. If you get graphics artifacts,'
+              'Using hardware rendering with device ${device.name}. If you get graphics artifacts, '
               'consider enabling software rendering with "--enable-software-rendering".'
             );
           }

packages/flutter_tools/test/android/android_device_test.dart

@@ -109,6 +109,7 @@ Use the 'android' tool to install them:
       hardware = 'goldfish';
       final AndroidDevice device = new AndroidDevice('test');
       expect(await device.isLocalEmulator, true);
+      expect(await device.supportsHardwareRendering, true);
     }, overrides: <Type, Generator>{
       ProcessManager: () => mockProcessManager,
     });
@@ -125,6 +126,7 @@ Use the 'android' tool to install them:
       buildCharacteristics = 'att,emulator';
       final AndroidDevice device = new AndroidDevice('test');
       expect(await device.isLocalEmulator, true);
+      expect(await device.supportsHardwareRendering, true);
     }, overrides: <Type, Generator>{
       ProcessManager: () => mockProcessManager,
     });