[profiler] Add extra CHECK to track down crbug.com/665398

src/profiler/profile-generator-inl.h

 // Copyright 2010 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.
 
 #ifndef V8_PROFILER_PROFILE_GENERATOR_INL_H_
 #define V8_PROFILER_PROFILE_GENERATOR_INL_H_
 
 #include "src/profiler/profile-generator.h"
 
 namespace v8 {
 namespace internal {
 
 CodeEntry::CodeEntry(CodeEventListener::LogEventsAndTags tag, const char* name,
                      const char* name_prefix, const char* resource_name,
                      int line_number, int column_number,
                      JITLineInfoTable* line_info, Address instruction_start)
     : bit_field_(TagField::encode(tag) |
                  BuiltinIdField::encode(Builtins::builtin_count)),
       name_prefix_(name_prefix),
       name_(name),
       resource_name_(resource_name),
       line_number_(line_number),
       column_number_(column_number),
       script_id_(v8::UnboundScript::kNoScriptId),
       position_(0),
       bailout_reason_(kEmptyBailoutReason),
       deopt_reason_(kNoDeoptReason),
       deopt_id_(kNoDeoptimizationId),
       line_info_(line_info),
-      instruction_start_(instruction_start) {}
+      instruction_start_(instruction_start) {
+// TODO(alph): Extra check to help catch crbug.com/665398
+// Remove before 5.8 branch
+#if V8_MAJOR_VERSION == 5 && V8_MINOR_VERSION == 7
+  CHECK(name);
+#endif
+}
 
 ProfileNode::ProfileNode(ProfileTree* tree, CodeEntry* entry,
                          ProfileNode* parent)
     : tree_(tree),
       entry_(entry),
       self_ticks_(0),
       children_(CodeEntriesMatch),
       parent_(parent),
       id_(tree->next_node_id()),
       line_ticks_(LineTickMatch) {
   tree_->EnqueueNode(this);
 }
 
 inline unsigned ProfileNode::function_id() const {
   return tree_->GetFunctionId(this);
 }
 
 inline Isolate* ProfileNode::isolate() const { return tree_->isolate(); }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PROFILER_PROFILE_GENERATOR_INL_H_