Drop the restriction on same forward and reverse sample rate on the AudioFrame interface of the APM

webrtc/modules/audio_processing/audio_processing_impl.cc

Index: webrtc/modules/audio_processing/audio_processing_impl.cc
diff --git a/webrtc/modules/audio_processing/audio_processing_impl.cc b/webrtc/modules/audio_processing/audio_processing_impl.cc
index a7c120f3956b13f0c4a798a71f961453979dc213..fed3f61564d4e59f0756dd78f553b46c7bddc942 100644
--- a/webrtc/modules/audio_processing/audio_processing_impl.cc
+++ b/webrtc/modules/audio_processing/audio_processing_impl.cc
@@ -871,11 +871,6 @@ int AudioProcessingImpl::AnalyzeReverseStream(AudioFrame* frame) {
       frame->sample_rate_hz_ != kSampleRate48kHz) {
     return kBadSampleRateError;
   }
-  // This interface does not tolerate different forward and reverse rates.
-  if (frame->sample_rate_hz_ !=
-      formats_.api_format.input_stream().sample_rate_hz()) {
-    return kBadSampleRateError;
-  }
 
   if (frame->num_channels_ <= 0) {
     return kBadNumberChannelsError;