Modify the test cases

Use SystemClock.uptimeMillis() replacing System.currentTimeMillis()
to get the timestamp.

Bug: 149271120
Test: atest AccessibilityTakeScreenshotTest
Change-Id: I188ea2bc88f5e665608ed842a1f4cd7b9ce3ed92
diff --git a/tests/accessibilityservice/src/android/accessibilityservice/cts/AccessibilityTakeScreenshotTest.java b/tests/accessibilityservice/src/android/accessibilityservice/cts/AccessibilityTakeScreenshotTest.java
index c67d8c2..b694767 100644
--- a/tests/accessibilityservice/src/android/accessibilityservice/cts/AccessibilityTakeScreenshotTest.java
+++ b/tests/accessibilityservice/src/android/accessibilityservice/cts/AccessibilityTakeScreenshotTest.java
@@ -28,6 +28,7 @@
 import android.graphics.ColorSpace;
 import android.graphics.Point;
 import android.hardware.HardwareBuffer;
+import android.os.SystemClock;
 import android.view.Display;
 import android.view.WindowManager;
 
@@ -77,7 +78,7 @@
 
     @Test
     public void testTakeScreenshot_GetScreenshotResult() {
-        mStartTestingTime = System.currentTimeMillis();
+        mStartTestingTime = SystemClock.uptimeMillis();
         Consumer<AccessibilityService.ScreenshotResult> screenshotConsumer =
                 new TakeScreenshotConsumer();
         mService.takeScreenshot(Display.DEFAULT_DISPLAY, mContext.getMainExecutor(),