Update abseil-cpp to a new upstream

Actually update to bf7fc9986e20f664958fc227547fd8d2fdcf863e

Change #754 didn't completely do this.

This makes the rest of the sources match optional, which was imported at
this change in #1083.

Also add:
  absl/types/optional_test.cc
  absl/types/CMakeLists.txt
  absl/utility/CMakeLists.txt

1 files changed, 8 insertions, 2 deletions

diff --git a/Firestore/third_party/abseil-cpp/absl/strings/substitute_test.cc b/Firestore/third_party/abseil-cpp/absl/strings/substitute_test.cc
index a6d7d7b..7c9af6b 100644
--- a/Firestore/third_party/abseil-cpp/absl/strings/substitute_test.cc
+++ b/Firestore/third_party/abseil-cpp/absl/strings/substitute_test.cc
@@ -46,8 +46,14 @@ TEST(SubstituteTest, Substitute) {
   // Pointer.
   const int* int_p = reinterpret_cast<const int*>(0x12345);
   std::string str = absl::Substitute("$0", int_p);
-  EXPECT_EQ(absl::StrCat("0x", absl::Hex(reinterpret_cast<intptr_t>(int_p))),
-            str);
+  EXPECT_EQ(absl::StrCat("0x", absl::Hex(int_p)), str);
+
+  // Volatile Pointer.
+  // Like C++ streamed I/O, such pointers implicitly become bool
+  volatile int vol = 237;
+  volatile int *volatile volptr = &vol;
+  str = absl::Substitute("$0", volptr);
+  EXPECT_EQ("true", str);
 
   // null is special. StrCat prints 0x0. Substitute prints NULL.
   const uint64_t* null_p = nullptr;