ART: Do not compile swap file functionality on Mac

Bug: 18596910

(cherry picked from commit 8a9f0049821803051201edebc6d9a0f0639756c3)

Change-Id: Ic06429f41840ce318cfaa837efecc69c2076440e
diff --git a/compiler/utils/swap_space.cc b/compiler/utils/swap_space.cc
index 19338c0..fc51435 100644
--- a/compiler/utils/swap_space.cc
+++ b/compiler/utils/swap_space.cc
@@ -131,6 +131,7 @@
 }
 
 SpaceChunk SwapSpace::NewFileChunk(size_t min_size) {
+#if !defined(__APPLE__)
   size_t next_part = std::max(RoundUp(min_size, kPageSize), RoundUp(kMininumMapSize, kPageSize));
   int result = TEMP_FAILURE_RETRY(ftruncate64(fd_, size_ + next_part));
   if (result != 0) {
@@ -151,6 +152,11 @@
   SpaceChunk new_chunk = {ptr, next_part};
   maps_.push_back(new_chunk);
   return new_chunk;
+#else
+  UNUSED(kMininumMapSize);
+  LOG(FATAL) << "No swap file support on the Mac.";
+  return {nullptr, 0U};  // NOLINT [readability/braces] [4]
+#endif
 }
 
 // TODO: Full coalescing.