[test] Test expectations in cctest should use CHECK and not DCHECK.

test/cctest/test-sampler-api.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Tests the sampling API in include/v8.h
 
 // TODO(mythria): Remove this define after this flag is turned on globally
 #define V8_IMMINENT_DEPRECATION_WARNINGS
 
 #include <map>
@@ skipping 76 matching lines @@
  public:
   struct CodeEventEntry {
     std::string name;
     const void* code_start;
     size_t code_len;
   };
   typedef std::map<const void*, CodeEventEntry> CodeEntries;
 
   explicit SamplingTestHelper(const std::string& test_function)
       : sample_is_taken_(false), isolate_(CcTest::isolate()) {
-    DCHECK(!instance_);
+    CHECK(!instance_);
     instance_ = this;
     v8::HandleScope scope(isolate_);
     v8::Local<v8::ObjectTemplate> global = v8::ObjectTemplate::New(isolate_);
     global->Set(v8_str("CollectSample"),
                 v8::FunctionTemplate::New(isolate_, CollectSample));
     LocalContext env(isolate_, NULL, global);
     isolate_->SetJitCodeEventHandler(v8::kJitCodeEventDefault,
                                      JitCodeEventHandler);
     CompileRun(v8_str(test_function.c_str()));
   }
@@ skipping 137 matching lines @@
 
   const SamplingTestHelper::CodeEventEntry* entry;
   entry = helper.FindEventEntry(sample.begin()[0]);
   CHECK(entry);
   CHECK(std::string::npos != entry->name.find("test_sampler_api_inner"));
 
   entry = helper.FindEventEntry(sample.begin()[1]);
   CHECK(entry);
   CHECK(std::string::npos != entry->name.find("test_sampler_api_outer"));
 }