Compile some tests for the host

Compile some tests for the host to ease debugging with valgrind or gdb.

Bug: 27208635
Change-Id: Ib46fcfa333ceb721f26efca00b2fa60b9fba44e6
(cherry picked from commit b8e20f557f315d2ab5e21f7bf70657bb16d5d42d)
diff --git a/libmemunreachable/Allocator.cpp b/libmemunreachable/Allocator.cpp
index b75f1e5..68f654c 100644
--- a/libmemunreachable/Allocator.cpp
+++ b/libmemunreachable/Allocator.cpp
@@ -370,11 +370,11 @@
 }
 
 void* HeapImpl::AllocLocked(size_t size) {
-  if (__predict_false(size > kMaxBucketAllocationSize)) {
+  if (size > kMaxBucketAllocationSize) {
     return MapAlloc(size);
   }
   int bucket = size_to_bucket(size);
-  if (__predict_false(free_chunks_[bucket].empty())) {
+  if (free_chunks_[bucket].empty()) {
     Chunk *chunk = new Chunk(this, bucket);
     free_chunks_[bucket].insert(chunk->node_);
   }