Always pass arguments to INSTANTIATE_TEST_SUITE_P.

Passing an empty arg is working at the moment but it is not
guaranteed to continue to work in the future.

This CL has been generated with:
git grep -l "INSTANTIATE_TEST_SUITE_P(," | xargs sed -i \
    "s/INSTANTIATE_TEST_SUITE_P(,/INSTANTIATE_TEST_SUITE_P(All,/g"

Bug: None
Change-Id: Icd2fb9d9d29aed5d692a234124bd990d0f097db4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/153890
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29282}
diff --git a/pc/rtc_stats_collector_unittest.cc b/pc/rtc_stats_collector_unittest.cc
index 02382cb..1420fcc 100644
--- a/pc/rtc_stats_collector_unittest.cc
+++ b/pc/rtc_stats_collector_unittest.cc
@@ -2633,7 +2633,7 @@
   EXPECT_TRUE(report->Get(*remote_inbound_rtp.transport_id));
 }
 
-INSTANTIATE_TEST_SUITE_P(,
+INSTANTIATE_TEST_SUITE_P(All,
                          RTCStatsCollectorTestWithParamKind,
                          ::testing::Values(cricket::MEDIA_TYPE_AUDIO,    // "/0"
                                            cricket::MEDIA_TYPE_VIDEO));  // "/1"