Fix Brotli warnings on Windows

third_party/brotli/enc/cluster.h

 /* Copyright 2013 Google Inc. All Rights Reserved.
 
    Distributed under MIT license.
    See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
 */
 
 // Functions for clustering similar histograms together.
 
 #ifndef BROTLI_ENC_CLUSTER_H_
 #define BROTLI_ENC_CLUSTER_H_
@@ skipping 45 matching lines @@
                            size_t* num_pairs) {
   if (idx1 == idx2) {
     return;
   }
   if (idx2 < idx1) {
     uint32_t t = idx2;
     idx2 = idx1;
     idx1 = t;
   }
   bool store_pair = false;
-  HistogramPair p;
+  HistogramPair p = {};
   p.idx1 = idx1;
   p.idx2 = idx2;
   p.cost_diff = 0.5 * ClusterCostDiff(cluster_size[idx1], cluster_size[idx2]);
   p.cost_diff -= out[idx1].bit_cost_;
   p.cost_diff -= out[idx2].bit_cost_;
 
   if (out[idx1].total_count_ == 0) {
     p.cost_combo = out[idx2].bit_cost_;
     store_pair = true;
   } else if (out[idx2].total_count_ == 0) {
@@ skipping 244 matching lines @@
 
   // Convert the context map to a canonical form.
   size_t num_histograms =
       HistogramReindex(&(*out)[0], &(*histogram_symbols)[0], in_size);
   out->resize(num_histograms);
 }
 
 }  // namespace brotli
 
 #endif  // BROTLI_ENC_CLUSTER_H_