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

BUG=chromium:665398

Review-Url: https://codereview.chromium.org/2556833003
Cr-Commit-Position: refs/heads/master@{#41545}

src/profiler/profile-generator-inl.h

@@ -27,7 +27,13 @@ CodeEntry::CodeEntry(CodeEventListener::LogEventsAndTags tag, const char* name,
       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)

src/profiler/profile-generator.cc

@@ -424,6 +424,11 @@ namespace {
 void BuildNodeValue(const ProfileNode* node, TracedValue* value) {
   const CodeEntry* entry = node->entry();
   value->BeginDictionary("callFrame");
+// 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(entry->name());
+#endif
   value->SetString("functionName", entry->name());
   if (*entry->resource_name()) {
     value->SetString("url", entry->resource_name());