Pass --harmony-object-observe in tests that depend on it

test/cctest/test-debug.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 7935 matching lines @@
       "var r;"
       "p.chain(function() { r = 'resolved'; },"
       "        function(e) { r = 'rejected' + e; });");
   CHECK(
       CompileRun("r")->Equals(context, v8_str("rejectedrejection")).FromJust());
   CHECK_EQ(1, exception_event_counter);
 }
 
 
 TEST(DebugBreakOnExceptionInObserveCallback) {
+  i::FLAG_harmony_object_observe = true;
   DebugLocalContext env;
   v8::Isolate* isolate = env->GetIsolate();
   v8::HandleScope scope(isolate);
   v8::Debug::SetDebugEventListener(isolate, &DebugEventCountException);
   v8::Local<v8::Context> context = env.context();
   // Break on uncaught exception
   ChangeBreakOnException(false, true);
   exception_event_counter = 0;
 
   v8::Local<v8::FunctionTemplate> fun =
@@ skipping 88 matching lines @@
   CompileRun("function foo() {}; foo();");
   --after_compile_handler_depth;
 }
 
 
 TEST(NoInterruptsInDebugListener) {
   DebugLocalContext env;
   v8::Debug::SetDebugEventListener(env->GetIsolate(), NoInterruptsOnDebugEvent);
   CompileRun("void(0);");
 }