Squashed 'src/leveldb/' changes from 936b461..e991315

e991315 Merge upstream LevelDB 1.15.
0cfb990 Release LevelDB 1.15
02ac9f1 Merge upstream LevelDB 1.14.
0b9a89f Release LevelDB 1.14

git-subtree-dir: src/leveldb
git-subtree-split: e991315d7fe4ca84a98902578106cbffa3dcccfd

util/arena.cc

@@ -40,7 +40,7 @@ char* Arena::AllocateFallback(size_t bytes) {
 }
 
 char* Arena::AllocateAligned(size_t bytes) {
-  const int align = sizeof(void*);    // We'll align to pointer size
+  const int align = (sizeof(void*) > 8) ? sizeof(void*) : 8;
   assert((align & (align-1)) == 0);   // Pointer size should be a power of 2
   size_t current_mod = reinterpret_cast<uintptr_t>(alloc_ptr_) & (align-1);
   size_t slop = (current_mod == 0 ? 0 : align - current_mod);