Reduce the runtime of some ACM tests in modules_tests

webrtc/modules/audio_coding/test/iSACTest.cc

 /*
  *  Copyright (c) 2012 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.
  */
 
 #include "webrtc/modules/audio_coding/test/iSACTest.h"
 
 #include <ctype.h>
 #include <stdio.h>
 #include <string.h>
 
 #if _WIN32
 #include <windows.h>
 #elif WEBRTC_LINUX
 #include <time.h>
 #else
 #include <sys/time.h>
 #include <time.h>
 #endif
 
+#include "webrtc/base/checks.h"
 #include "webrtc/modules/audio_coding/acm2/acm_common_defs.h"
 #include "webrtc/modules/audio_coding/test/utility.h"
 #include "webrtc/system_wrappers/include/event_wrapper.h"
 #include "webrtc/system_wrappers/include/tick_util.h"
 #include "webrtc/system_wrappers/include/trace.h"
 #include "webrtc/test/testsupport/fileutils.h"
 
 namespace webrtc {
 
 void SetISACConfigDefault(ACMTestISACConfig& isacConfig) {
@@ skipping 74 matching lines @@
   EXPECT_EQ(0, _acmB->RegisterTransportCallback(_channel_B2A.get()));
   _channel_B2A->RegisterReceiverACM(_acmA.get());
 
   file_name_swb_ = webrtc::test::ResourcePath("audio_coding/testfile32kHz",
                                               "pcm");
 
   EXPECT_EQ(0, _acmB->RegisterSendCodec(_paramISAC16kHz));
   EXPECT_EQ(0, _acmA->RegisterSendCodec(_paramISAC32kHz));
 
   _inFileA.Open(file_name_swb_, 32000, "rb");
+  static const int kTestLengthMs = 500;
+  const int test_length_blocks = rtc::CheckedDivExact(kTestLengthMs, 10);
+  _inFileA.SetNum10MsBlocksToRead(test_length_blocks);
+  // Fast-forward 1 second (100 blocks) since the files start with silence.
+  _inFileA.FastForward(100);
   std::string fileNameA = webrtc::test::OutputPath() + "testisac_a.pcm";
   std::string fileNameB = webrtc::test::OutputPath() + "testisac_b.pcm";
   _outFileA.Open(fileNameA, 32000, "wb");
   _outFileB.Open(fileNameB, 32000, "wb");
 
   while (!_inFileA.EndOfFile()) {
     Run10ms();
   }
   CodecInst receiveCodec;
   EXPECT_EQ(0, _acmA->ReceiveCodec(&receiveCodec));
@@ skipping 200 matching lines @@
       numSendCodecChanged++;
     }
   }
   _outFileA.Close();
   _outFileB.Close();
   _inFileA.Close();
   _inFileB.Close();
 }
 
 }  // namespace webrtc