Support Samsung phone when getting device `wakefulness` status (#98146)

dev/devicelab/lib/framework/devices.dart

@@ -505,7 +505,10 @@ class AndroidDevice extends Device {
   /// See: https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/os/PowerManagerInternal.java
   Future<String> _getWakefulness() async {
     final String powerInfo = await shellEval('dumpsys', <String>['power']);
-    final String wakefulness = grep('mWakefulness=', from: powerInfo).single.split('=')[1].trim();
+    // A motoG4 phone returns `mWakefulness=Awake`.
+    // A Samsung phone returns `getWakefullnessLocked()=Awake`.
+    final RegExp wakefulnessRegexp = RegExp(r'.*(mWakefulness=|getWakefulnessLocked\(\)=).*');
+    final String wakefulness = grep(wakefulnessRegexp, from: powerInfo).single.split('=')[1].trim();
     return wakefulness;
   }
 

dev/devicelab/test/adb_test.dart

@@ -40,6 +40,12 @@ void main() {
         expect(await device.isAsleep(), isFalse);
       });
 
+      test('reads Awake - samsung devices', () async {
+        FakeDevice.pretendAwakeSamsung();
+        expect(await device.isAwake(), isTrue);
+        expect(await device.isAsleep(), isFalse);
+      });
+
       test('reads Asleep', () async {
         FakeDevice.pretendAsleep();
         expect(await device.isAwake(), isFalse);
@@ -190,6 +196,12 @@ class FakeDevice extends AndroidDevice {
     ''';
   }
 
+  static void pretendAwakeSamsung() {
+    output = '''
+      getWakefulnessLocked()=Awake
+    ''';
+  }
+
   static void pretendAsleep() {
     output = '''
       mWakefulness=Asleep