Fix CQS signal performance-inefficient-vector-operation in fbcode/mapillary/opensfm

Differential Revision: D90845003

fbshipit-source-id: 68dfb8f4d46f11209836399617be9dc17cf24a44

Author: generatedunixname89002005287564

opensfm/src/bundle/src/bundle_adjuster.cc

@@ -1133,6 +1133,7 @@ void BundleAdjuster::ComputeCovariances(ceres::Problem* problem) {
     ceres::Covariance covariance(options);
 
     std::vector<std::pair<const double*, const double*>> covariance_blocks;
+    covariance_blocks.reserve(shots_.size());
     for (auto& i : shots_) {
       covariance_blocks.emplace_back(
           i.second.GetRigInstance()->GetValueData().data(),