[llvm] [ADT] Make Zippy more iterator-like for lifetime safety (PR #112441)

[Jakub Kuderski via llvm-commits]

================
@@ -482,39 +482,26 @@ TEST(ZipIteratorTest, ZipEqualConstCorrectness) {
   EXPECT_THAT(first, ElementsAre(0, 0, 0));
   EXPECT_THAT(second, ElementsAre(true, true, true));
 
-  std::vector<bool> nemesis = {true, false, true};
-  const std::vector<bool> c_nemesis = nemesis;
-
-  for (auto &&[a, b, c, d] : zip_equal(first, c_first, nemesis, c_nemesis)) {
+  for (auto &&[a, b] : zip_equal(first, c_first)) {
     a = 2;
-    c = true;
     static_assert(!IsConstRef<decltype(a)>);
     static_assert(IsConstRef<decltype(b)>);
-    static_assert(!IsBoolConstRef<decltype(c)>);
-    static_assert(IsBoolConstRef<decltype(d)>);
----------------
kuhar wrote:

Why is this removed?

https://github.com/llvm/llvm-project/pull/112441