Add --es-staging flag

test/cctest/test-decls.cc

Index: test/cctest/test-decls.cc
diff --git a/test/cctest/test-decls.cc b/test/cctest/test-decls.cc
index 1f22c9ff3a0eb1b5efe9aaa4e8bcf9173bccb29c..d6738a31aec11e01f79ca2e02291dc06c1cb7fb5 100644
--- a/test/cctest/test-decls.cc
+++ b/test/cctest/test-decls.cc
@@ -557,7 +557,6 @@ class ExistsInPrototypeContext: public DeclarationContext {
 
 
 TEST(ExistsInPrototype) {
-  i::FLAG_es52_globals = true;
   HandleScope scope(CcTest::isolate());
 
   // Sanity check to make sure that the holder of the interceptor
@@ -620,7 +619,6 @@ class AbsentInPrototypeContext: public DeclarationContext {
 
 
 TEST(AbsentInPrototype) {
-  i::FLAG_es52_globals = true;
   v8::V8::Initialize();
   HandleScope scope(CcTest::isolate());
 
@@ -668,7 +666,6 @@ class ExistsInHiddenPrototypeContext: public DeclarationContext {
 
 
 TEST(ExistsInHiddenPrototype) {
-  i::FLAG_es52_globals = true;
   HandleScope scope(CcTest::isolate());
 
   { ExistsInHiddenPrototypeContext context;