Pass isolate output dir to gtest-parallel-wrapper.py

tools-webrtc/mb/mb.py

Index: tools-webrtc/mb/mb.py
diff --git a/tools-webrtc/mb/mb.py b/tools-webrtc/mb/mb.py
index eb92f239f0c035586feae16caad3aad4ab4fb7f2..49f681f9dc130e59029cc8350ef507ab076f4086 100755
--- a/tools-webrtc/mb/mb.py
+++ b/tools-webrtc/mb/mb.py
@@ -1100,14 +1100,17 @@ class MetaBuildWrapper(object):
 
       gtest_parallel = (test_type != 'non_parallel_console_test_launcher' and
                         not memcheck)
-      gtest_parallel_wrapper = [
-          '../../third_party/gtest-parallel/gtest-parallel-wrapper.py'
-      ]
       if gtest_parallel:
         extra_files += [
             '../../third_party/gtest-parallel/gtest-parallel',
             '../../third_party/gtest-parallel/gtest-parallel-wrapper.py',
         ]
+        sep = '\\' if self.platform == 'win32' else '/'
+        output_dir = '${ISOLATED_OUTDIR}' + sep + 'test_logs'
+        gtest_parallel_wrapper = [
+            '../../third_party/gtest-parallel/gtest-parallel-wrapper.py',
+            '--output_dir=%s' % output_dir,
+        ]
 
       asan = 'is_asan=true' in vals['gn_args']
       msan = 'is_msan=true' in vals['gn_args']