Fixing warning C4267 on Win (more_configs).

This is a follow-up of https://webrtc-review.googlesource.com/c/src/+/12921.

Bug: chromium:759980
Change-Id: Ifd39adb6541c0c7e0337f587a8b34b84a07331ed
Reviewed-on: https://webrtc-review.googlesource.com/13122
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20341}
diff --git a/modules/audio_coding/acm2/acm_receiver_unittest.cc b/modules/audio_coding/acm2/acm_receiver_unittest.cc
index 8fbea84..c420c7e 100644
--- a/modules/audio_coding/acm2/acm_receiver_unittest.cc
+++ b/modules/audio_coding/acm2/acm_receiver_unittest.cc
@@ -108,7 +108,7 @@
     last_packet_send_timestamp_ = timestamp_;
     while (!packet_sent_) {
       frame.timestamp_ = timestamp_;
-      timestamp_ += frame.samples_per_channel_;
+      timestamp_ += rtc::checked_cast<uint32_t>(frame.samples_per_channel_);
       ASSERT_GE(acm_->Add10MsData(frame), 0);
     }
   }
@@ -175,8 +175,9 @@
   for (size_t n = 0; n < codecs_.size(); ++n) {
     if (n & 0x1) {  // Just add codecs with odd index.
       EXPECT_EQ(
-          0, receiver_->AddCodec(n, codecs_[n].pltype, codecs_[n].channels,
-                                 codecs_[n].plfreq, NULL, codecs_[n].plname));
+          0, receiver_->AddCodec(rtc::checked_cast<int>(n), codecs_[n].pltype,
+                                 codecs_[n].channels, codecs_[n].plfreq, NULL,
+                                 codecs_[n].plname));
     }
   }
   // Get codec and compare.
@@ -338,7 +339,7 @@
         EXPECT_EQ(0,
                   receiver_->GetAudio(output_sample_rate_hz, &frame, &muted));
         EXPECT_EQ(expected_output_ts, frame.timestamp_);
-        expected_output_ts += 10 * samples_per_ms;
+        expected_output_ts += rtc::checked_cast<uint32_t>(10 * samples_per_ms);
         EXPECT_EQ(10 * samples_per_ms, frame.samples_per_channel_);
         EXPECT_EQ(output_sample_rate_hz, frame.sample_rate_hz_);
         EXPECT_EQ(output_channels, frame.num_channels_);