Improving screenshot path

Change-Id: If61bbf0bbc8ace31142bc0e2d598d72ce48de360
diff --git a/tests/src/com/android/launcher3/util/rule/FailureWatcher.java b/tests/src/com/android/launcher3/util/rule/FailureWatcher.java
index eef2f24..e7a2bca 100644
--- a/tests/src/com/android/launcher3/util/rule/FailureWatcher.java
+++ b/tests/src/com/android/launcher3/util/rule/FailureWatcher.java
@@ -15,7 +15,6 @@
 
 public class FailureWatcher extends TestWatcher {
     private static final String TAG = "FailureWatcher";
-    private static int sScreenshotCount = 0;
     final private UiDevice mDevice;
 
     public FailureWatcher(UiDevice device) {
@@ -40,7 +39,8 @@
     protected void failed(Throwable e, Description description) {
         if (mDevice == null) return;
         final String pathname = getInstrumentation().getTargetContext().
-                getFilesDir().getPath() + "/TaplTestScreenshot" + sScreenshotCount++ + ".png";
+                getFilesDir().getPath() + "/TestScreenshot-" + description.getMethodName()
+                + ".png";
         Log.e(TAG, "Failed test " + description.getMethodName() +
                 ", screenshot will be saved to " + pathname +
                 ", track trace is below, UI object dump is further below:\n" +