ac6fbf2c83578129a0397d0d0dc9b1c6bdb30701 tidy: use modernize-use-default-member-init (fanquake)
7aa40f55636be565441a9e0af8de0a346bfa4da2 refactor: use C++11 default initializers (fanquake)
Pull request description:
Refactor and then enable [`modernize-use-default-member-init`](https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-default-member-init.html) in our `clang-tidy` job.
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Tree-SHA512: 536b406f20639f8c588fe9e96175ec60c7bb825506b2670b562370b2f572801c24203c483443be3c199e1b958c0765d4532e57c57a4e78689162a1dd422d844f