Correct clean up in android perf runner.

tools/run_perf.py

 #!/usr/bin/env python
 # Copyright 2014 the V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """
 Performance runner for d8.
 
 Call e.g. with tools/run-perf.py --arch ia32 some_suite.json
 
@@ skipping 498 matching lines @@
   def PreExecution(self):
     perf = perf_control.PerfControl(self.device)
     perf.SetHighPerfMode()
 
     # Remember what we have already pushed to the device.
     self.pushed = set()
 
   def PostExecution(self):
     perf = perf_control.PerfControl(self.device)
     perf.SetDefaultPerfMode()
-    self.device.RunShellCommand(
-        ["rm", "-rf", "*"],
-        cwd=AndroidPlatform.DEVICE_DIR,
-    )
+    self.device.RunShellCommand(["rm", "-rf", AndroidPlatform.DEVICE_DIR])
 
   def _PushFile(self, host_dir, file_name, target_rel="."):
     file_on_host = os.path.join(host_dir, file_name)
     file_on_device = os.path.join(
         AndroidPlatform.DEVICE_DIR, target_rel, file_name)
 
     # Only push files not yet pushed in one execution.
     if file_on_host in self.pushed:
       return
     else:
@@ skipping 141 matching lines @@
 
   if options.json_test_results:
     results.WriteToFile(options.json_test_results)
   else:  # pragma: no cover
     print results
 
   return min(1, len(results.errors))
 
 if __name__ == "__main__":  # pragma: no cover
   sys.exit(Main(sys.argv[1:]))