Split content script injections into multiple tasks

third_party/WebKit/public/web/WebScriptExecutionCallback.h

 // Copyright 2014 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.
 
 #ifndef WebScriptExecutionCallback_h
 #define WebScriptExecutionCallback_h
 
 namespace v8 {
 class Value;
 template <class T>
 class Local;
 }
 
 namespace blink {
 
 template <typename T>
 class WebVector;
 
 class WebScriptExecutionCallback {
  public:
   virtual ~WebScriptExecutionCallback() {}
 
+  // Method to be invoked when the asynchronous script is about to execute.
+  virtual void willExecute() {}
+
   // Method to be invoked when the asynchronous script execution is complete.
   // After function call all objects in vector will be collected
   virtual void completed(const WebVector<v8::Local<v8::Value>>&) {}
 };
 
 }  // namespace blink
 
 #endif  // WebScriptExecutionCallback_h