Moved zones and zone related stuff in its own directory.

test/unittests/wasm/ast-decoder-unittest.cc

Index: test/unittests/wasm/ast-decoder-unittest.cc
diff --git a/test/unittests/wasm/ast-decoder-unittest.cc b/test/unittests/wasm/ast-decoder-unittest.cc
index cd13272641482c53da681f3a9d08fe3ead823277..f508094ef361cfc4859ca635ffa9bb12391e9692 100644
--- a/test/unittests/wasm/ast-decoder-unittest.cc
+++ b/test/unittests/wasm/ast-decoder-unittest.cc
@@ -2493,7 +2493,7 @@ typedef ZoneVector<LocalType> LocalTypeMap;
 
 class LocalDeclDecoderTest : public TestWithZone {
  public:
-  base::AccountingAllocator allocator;
+  v8::internal::AccountingAllocator allocator;
 
   size_t ExpectRun(LocalTypeMap map, size_t pos, LocalType expected,
                    size_t count) {