RenderWriter checks number of bands before inserting AudioBuffer.

Temporary work-around for bug webrtc:8759.

Bug: webrtc:8759
Change-Id: Ia830c7e19d7bb332d760f52d62757a443761dc3e
Reviewed-on: https://webrtc-review.googlesource.com/39920
Reviewed-by: Per Ã…hgren <peah@webrtc.org>
Commit-Queue: Gustaf Ullberg <gustaf@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21639}
diff --git a/modules/audio_processing/aec3/echo_canceller3.cc b/modules/audio_processing/aec3/echo_canceller3.cc
index 100ed27..e365949 100644
--- a/modules/audio_processing/aec3/echo_canceller3.cc
+++ b/modules/audio_processing/aec3/echo_canceller3.cc
@@ -184,6 +184,12 @@
 void EchoCanceller3::RenderWriter::Insert(AudioBuffer* input) {
   RTC_DCHECK_EQ(1, input->num_channels());
   RTC_DCHECK_EQ(frame_length_, input->num_frames_per_band());
+  RTC_DCHECK_EQ(num_bands_, input->num_bands());
+
+  // TODO(bugs.webrtc.org/8759) Temporary work-around.
+  if (num_bands_ != static_cast<int>(input->num_bands()))
+    return;
+
   data_dumper_->DumpWav("aec3_render_input", frame_length_,
                         &input->split_bands_f(0)[0][0],
                         LowestBandRate(sample_rate_hz_), 1);