Clean up compiler dispatcher job a bit

test/unittests/compiler-dispatcher/compiler-dispatcher-job-unittest.cc

 // Copyright 2016 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.
 
 #include <memory>
 
 #include "src/compiler-dispatcher/compiler-dispatcher-job.h"
 #include "src/flags.h"
 #include "src/isolate-inl.h"
 #include "test/unittests/test-utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace v8 {
 namespace internal {
 
 typedef TestWithContext CompilerDispatcherJobTest;
 
 namespace {
 
 class ScriptResource : public v8::String::ExternalOneByteStringResource {
  public:
   ScriptResource(const char* data, size_t length)
       : data_(data), length_(length) {}
+  ~ScriptResource() override = default;
 
-  const char* data() const { return data_; }
-  size_t length() const { return length_; }
+  const char* data() const override { return data_; }
+  size_t length() const override { return length_; }
 
  private:
   const char* data_;
   size_t length_;
 
   DISALLOW_COPY_AND_ASSIGN(ScriptResource);
 };
 
 Handle<JSFunction> CreateFunction(
     Isolate* isolate, ExternalOneByteString::Resource* maybe_resource) {
@@ skipping 47 matching lines @@
 
   ASSERT_TRUE(job->status() == CompileJobStatus::kInitial);
   job->PrepareToParseOnMainThread();
   ASSERT_TRUE(job->status() == CompileJobStatus::kReadyToParse);
   job->Parse();
   ASSERT_TRUE(job->status() == CompileJobStatus::kParsed);
 }
 
 }  // namespace internal
 }  // namespace v8