[Telemetry] Move from telemetry WaitFor to py_utils WaitFor

telemetry/telemetry/internal/backends/android_app_backend.py

Index: telemetry/telemetry/internal/backends/android_app_backend.py
diff --git a/telemetry/telemetry/internal/backends/android_app_backend.py b/telemetry/telemetry/internal/backends/android_app_backend.py
index 99be759a5297c2b0a0d2e4aacaa843a352c3a85a..04e4c4140c251a98cd607d6394fde00b3fc5d849 100644
--- a/telemetry/telemetry/internal/backends/android_app_backend.py
+++ b/telemetry/telemetry/internal/backends/android_app_backend.py
@@ -4,7 +4,6 @@
 
 import re
 
-from telemetry.core import util
 from telemetry.internal.app import android_process
 from telemetry.internal.backends import android_browser_backend_settings
 from telemetry.internal.backends import android_command_line_backend
@@ -13,6 +12,8 @@ from telemetry.internal.backends import app_backend
 from devil.android import app_ui
 from devil.android.sdk import intent
 
+import py_utils
+
 
 class AndroidAppBackend(app_backend.AppBackend):
 
@@ -53,7 +54,7 @@ class AndroidAppBackend(app_backend.AppBackend):
         force_stop=True,  # Ensure app was not running.
     )
     if has_ready_predicate:
-      util.WaitFor(is_app_ready, timeout=60)
+      py_utils.WaitFor(is_app_ready, timeout=60)
 
   def Start(self):
     """Start an Android app and wait for it to finish launching.