RTC_[D]CHECK_op: Remove "u" suffix on integer constants

webrtc/modules/audio_mixer/audio_frame_manipulator.cc

Index: webrtc/modules/audio_mixer/audio_frame_manipulator.cc
diff --git a/webrtc/modules/audio_mixer/audio_frame_manipulator.cc b/webrtc/modules/audio_mixer/audio_frame_manipulator.cc
index fca9a78b5039ba4e71f26fa6a27c864edf2d560a..255027478a72a68e60ca0a7ace7e78e6367e6eaa 100644
--- a/webrtc/modules/audio_mixer/audio_frame_manipulator.cc
+++ b/webrtc/modules/audio_mixer/audio_frame_manipulator.cc
@@ -31,7 +31,7 @@ void Ramp(float start_gain, float target_gain, AudioFrame* audio_frame) {
   RTC_DCHECK_GE(target_gain, 0.0f);
 
   size_t samples = audio_frame->samples_per_channel_;
-  RTC_DCHECK_LT(0u, samples);
+  RTC_DCHECK_LT(0, samples);
   float increment = (target_gain - start_gain) / samples;
   float gain = start_gain;
   for (size_t i = 0; i < samples; ++i) {
@@ -45,8 +45,8 @@ void Ramp(float start_gain, float target_gain, AudioFrame* audio_frame) {
 }
 
 void RemixFrame(size_t target_number_of_channels, AudioFrame* frame) {
-  RTC_DCHECK_GE(target_number_of_channels, 1u);
-  RTC_DCHECK_LE(target_number_of_channels, 2u);
+  RTC_DCHECK_GE(target_number_of_channels, 1);
+  RTC_DCHECK_LE(target_number_of_channels, 2);
   if (frame->num_channels_ == 1 && target_number_of_channels == 2) {
     AudioFrameOperations::MonoToStereo(frame);
   } else if (frame->num_channels_ == 2 && target_number_of_channels == 1) {