Add missing ABSL_CONST_INIT to variable definitions (#16355)

Firestore/core/src/core/direction.cc

@@ -18,12 +18,16 @@
 
 #include <ostream>
 
+#include "absl/base/attributes.h"
+
 namespace firebase {
 namespace firestore {
 namespace core {
 
-const Direction Direction::Ascending(Direction::AscendingModifier);
-const Direction Direction::Descending(Direction::DescendingModifier);
+ABSL_CONST_INIT const Direction
+    Direction::Ascending(Direction::AscendingModifier);
+ABSL_CONST_INIT const Direction
+    Direction::Descending(Direction::DescendingModifier);
 
 std::string Direction::CanonicalId() const {
   return comparison_modifier_ == AscendingModifier ? "asc" : "desc";

Firestore/core/src/local/lru_garbage_collector.cc

@@ -17,9 +17,11 @@
 #include "Firestore/core/src/local/lru_garbage_collector.h"
 
 #include <chrono>
+
 #include <queue>
 #include <string>
 #include <utility>
+#include "absl/base/attributes.h"
 
 #include "Firestore/core/include/firebase/firestore/timestamp.h"
 #include "Firestore/core/src/api/settings.h"
@@ -89,7 +91,7 @@ class RollingSequenceNumberBuffer {
 
 }  // namespace
 
-const ListenSequenceNumber kListenSequenceNumberInvalid = -1;
+ABSL_CONST_INIT const ListenSequenceNumber kListenSequenceNumberInvalid = -1;
 
 LruParams LruParams::Default() {
   return LruParams{100 * 1024 * 1024, 10, 1000};

Firestore/core/test/unit/testutil/testutil.cc

@@ -17,8 +17,11 @@
 #include "Firestore/core/test/unit/testutil/testutil.h"
 
 #include <algorithm>
+#include <cstdint>
+
 #include <chrono>
 #include <set>
+#include "absl/base/attributes.h"
 
 #include "Firestore/core/include/firebase/firestore/geo_point.h"
 #include "Firestore/core/include/firebase/firestore/timestamp.h"
@@ -93,7 +96,7 @@ constexpr const char* kDeleteSentinel = "<DELETE>";
 // the JDK (which is defined to normalize all NaNs to this value). This also
 // happens to be a common value for NAN in C++, but C++ does not require this
 // specific NaN value to be used, so we normalize.
-const uint64_t kCanonicalNanBits = 0x7ff8000000000000ULL;
+ABSL_CONST_INIT const uint64_t kCanonicalNanBits = 0x7ff8000000000000ULL;
 
 namespace details {