Fix event sending in pdfium_test.

testing/tools/test_runner.py

 #!/usr/bin/env python
 # Copyright 2016 The PDFium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import optparse
 import os
 import re
 import subprocess
 import sys
@@ skipping 73 matching lines @@
       cmd_to_run = common.DrMemoryWrapper(self.drmem_wrapper, input_root)
       cmd_to_run.extend([self.pdfium_test_path, pdf_path])
       subprocess.check_call(cmd_to_run, stdout=outfile)
 
     cmd = [sys.executable, self.text_diff_path, expected_txt_path, txt_path]
     return common.RunCommand(cmd)
 
 
   def TestPixel(self, input_root, pdf_path):
     cmd_to_run = common.DrMemoryWrapper(self.drmem_wrapper, input_root)
-    cmd_to_run.extend([self.pdfium_test_path, '--png', pdf_path])
+    cmd_to_run.extend([self.pdfium_test_path, '--send-events', '--png',
+                       pdf_path])
     return common.RunCommand(cmd_to_run)
 
 
   def HandleResult(self, input_filename, input_path, result):
     if self.test_suppressor.IsResultSuppressed(input_filename):
       if result:
         self.surprises.append(input_path)
     else:
       if not result:
         self.failures.append(input_path)
@@ skipping 72 matching lines @@
         print surprise;
 
     if self.failures:
       self.failures.sort()
       print '\n\nSummary of Failures:'
       for failure in self.failures:
         print failure
       return 1
 
     return 0