WIP: Reland CompiledScript, prototype compiling in a separate task.

third_party/WebKit/Source/bindings/core/v8/CompiledScript.cpp

+// Copyright 2017 The Chromium 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 "bindings/core/v8/CompiledScript.h"
+
+#include "bindings/core/v8/V8Binding.h"
+
+namespace blink {
+
+CompiledScript::CompiledScript(ExecutionContext* context,
+                               v8::Local<v8::Script> script,
+                               const ScriptSourceCode& sourceCode)
+    : ContextLifecycleObserver(context),
+      m_sourceCode(sourceCode),
+      m_script(toIsolate(context), script) {
+  DCHECK(!script.IsEmpty());
+}
+
+CompiledScript::~CompiledScript() = default;
+
+v8::Local<v8::Script> CompiledScript::getScript(
+    ExecutionContext* executionContext) const {
+  if (executionContext != getExecutionContext())
+    return v8::Local<v8::Script>();
+  return m_script.Get(toIsolate(executionContext));
+}
+
+void CompiledScript::contextDestroyed(ExecutionContext*) {
+  // Dump the persistent handle to the script. This prevents there from being
+  // an ownership cycle that keeps the context alive.
+  m_script.Reset();
+}
+
+}  // namespace blink