Add aecdump support to audioproc_f.

webrtc/modules/audio_processing/test/process_test.cc

Index: webrtc/modules/audio_processing/test/process_test.cc
diff --git a/webrtc/modules/audio_processing/test/process_test.cc b/webrtc/modules/audio_processing/test/process_test.cc
index 43165404c84587ce9d11aa739ddc60062f65a283..555d9d613306cf76281e58381cfa94b3a588dec2 100644
--- a/webrtc/modules/audio_processing/test/process_test.cc
+++ b/webrtc/modules/audio_processing/test/process_test.cc
@@ -636,8 +636,8 @@ void void_main(int argc, char* argv[]) {
         }
 
         if (!raw_output) {
-          // The WAV file needs to be reset every time, because it cant change
-          // it's sample rate or number of channels.
+          // The WAV file needs to be reset every time, because it can't change
+          // its sample rate or number of channels.
           output_wav_file.reset(new WavWriter(out_filename + ".wav",
                                               output_sample_rate,
                                               msg.num_output_channels()));