Support PNG and quality control in chrome.tabs.captureVisibleTab().

chrome/browser/extensions/extension_function.h

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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 CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_H_
 
 #include <string>
 #include <list>
 
 #include "base/values.h"
@@ skipping 157 matching lines @@
 
   void SendResponse(bool success);
 
   const ListValue* args_as_list() {
     return static_cast<ListValue*>(args_.get());
   }
   const DictionaryValue* args_as_dictionary() {
     return static_cast<DictionaryValue*>(args_.get());
   }
 
+  bool HasOptionalArgument(size_t index);
+
   // Note: After Run() returns, dispatcher() can be NULL.  Since these getters
   // rely on dispatcher(), make sure it is valid before using them.
   std::string extension_id();
   Profile* profile() const;
 
   // The arguments to the API. Only non-null if argument were specified.
   scoped_ptr<Value> args_;
 
   // The result of the API. This should be populated by the derived class before
   // SendResponse() is called.
@@ skipping 30 matching lines @@
   }
 
  protected:
   virtual ~SyncExtensionFunction() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SyncExtensionFunction);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_H_