Fix Chromium clang plugin warnings

webrtc/common_audio/sparse_fir_filter.cc

Index: webrtc/common_audio/sparse_fir_filter.cc
diff --git a/webrtc/common_audio/sparse_fir_filter.cc b/webrtc/common_audio/sparse_fir_filter.cc
index 5862b7cc6b7308c18e2001dc9c38949a1b554df4..a79da07b2d976781c24bd01719865d3ee9a7c30f 100644
--- a/webrtc/common_audio/sparse_fir_filter.cc
+++ b/webrtc/common_audio/sparse_fir_filter.cc
@@ -26,6 +26,8 @@ SparseFIRFilter::SparseFIRFilter(const float* nonzero_coeffs,
   RTC_CHECK_GE(sparsity, 1u);
 }
 
+SparseFIRFilter::~SparseFIRFilter() = default;
+
 void SparseFIRFilter::Filter(const float* in, size_t length, float* out) {
   // Convolves the input signal |in| with the filter kernel |nonzero_coeffs_|
   // taking into account the previous state.