Added forced zero AEC output after call startup and echo path changes

webrtc/modules/audio_processing/aec3/aec_state.cc

Index: webrtc/modules/audio_processing/aec3/aec_state.cc
diff --git a/webrtc/modules/audio_processing/aec3/aec_state.cc b/webrtc/modules/audio_processing/aec3/aec_state.cc
index 8e92f5fbdac3a4719428e1275bf966ca73b58151..1a9f66ffcb94d0bee478446820142a5fbfa91f28 100644
--- a/webrtc/modules/audio_processing/aec3/aec_state.cc
+++ b/webrtc/modules/audio_processing/aec3/aec_state.cc
@@ -97,6 +97,11 @@ void AecState::HandleEchoPathChange(
     echo_saturation_ = false;
     headset_detected_ = false;
     previous_max_sample_ = 0.f;
+
+    if (echo_path_variability.delay_change) {
+      force_zero_gain_counter_ = 0;
+      force_zero_gain_ = true;
+    }
   }
 }
 
@@ -117,6 +122,12 @@ void AecState::Update(const std::vector<std::array<float, kFftLengthBy2Plus1>>&
   active_render_blocks_ += active_render_block ? 1 : 0;
   --echo_path_change_counter_;
 
+  // Force zero echo suppression gain after an echo path change to allow at
+  // least some render data to be collected in order to avoid an initial echo
+  // burst.
+  constexpr size_t kZeroGainBlocksAfterChange = kNumBlocksPerSecond / 5;
+  force_zero_gain_ = (++force_zero_gain_counter_) < kZeroGainBlocksAfterChange;
+
   // Estimate delays.
   filter_delay_ = EstimateFilterDelay(adaptive_filter_frequency_response);
   external_delay_ =