Convert channel counts to size_t.

webrtc/voice_engine/test/auto_test/standard/codec_test.cc

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 32 matching lines @@
 }
 
 static bool IsNotViableSendCodec(const char* codec_name) {
   return !_stricmp(codec_name, "CN") ||
          !_stricmp(codec_name, "telephone-event") ||
          !_stricmp(codec_name, "red");
 }
 
 TEST_F(CodecTest, PcmuIsDefaultCodecAndHasTheRightValues) {
   EXPECT_EQ(0, voe_codec_->GetSendCodec(channel_, codec_instance_));
-  EXPECT_EQ(1, codec_instance_.channels);
+  EXPECT_EQ(1u, codec_instance_.channels);
   EXPECT_EQ(160, codec_instance_.pacsize);
   EXPECT_EQ(8000, codec_instance_.plfreq);
   EXPECT_EQ(0, codec_instance_.pltype);
   EXPECT_EQ(64000, codec_instance_.rate);
   EXPECT_STRCASEEQ("PCMU", codec_instance_.plname);
 }
 
 TEST_F(CodecTest, VoiceActivityDetectionIsOffByDefault) {
   bool vad_enabled = false;
   bool dtx_disabled = false;
@@ skipping 166 matching lines @@
         TEST_LOG("%d ", packet_size);
         TEST_LOG_FLUSH;
         at_least_one_succeeded = true;
         Sleep(CODEC_TEST_TIME);
       }
     }
     TEST_LOG("\n");
     EXPECT_TRUE(at_least_one_succeeded);
   }
 }