[profiler] fix memory leak for code entries for runtime callstats.

Track allocated code entries and delete at the end. This is what we
do in ProfileListener too.

R=alph@chromium.org, cbruni@chromium.org
BUG=v8:5753

Review-Url: https://codereview.chromium.org/2586923002
Cr-Commit-Position: refs/heads/master@{#41793}

src/profiler/profile-generator.cc

@@ -649,10 +649,15 @@ ProfileGenerator::ProfileGenerator(Isolate* isolate,
     DCHECK(counter->name());
     auto entry = new CodeEntry(CodeEventListener::FUNCTION_TAG, counter->name(),
                                CodeEntry::kEmptyNamePrefix, "native V8Runtime");
+    code_entries_.push_back(entry);
     code_map_.AddCode(reinterpret_cast<Address>(counter), entry, 1);
   }
 }
 
+ProfileGenerator::~ProfileGenerator() {
+  for (auto code_entry : code_entries_) delete code_entry;
+}
+
 void ProfileGenerator::RecordTickSample(const TickSample& sample) {
   std::vector<CodeEntry*> entries;
   // Conservatively reserve space for stack frames + pc + function + vm-state.

src/profiler/profile-generator.h

@@ -369,6 +369,7 @@ class CpuProfilesCollection {
 class ProfileGenerator {
  public:
   ProfileGenerator(Isolate* isolate, CpuProfilesCollection* profiles);
+  ~ProfileGenerator();
 
   void RecordTickSample(const TickSample& sample);
 
@@ -381,6 +382,7 @@ class ProfileGenerator {
   Isolate* isolate_;
   CpuProfilesCollection* profiles_;
   CodeMap code_map_;
+  std::vector<CodeEntry*> code_entries_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileGenerator);
 };