unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, OleCtrls, SHDocVw, MSHTML;

type
  TForm1 = class(TForm)
    Button1: TButton;
    WebBrowser1: TWebBrowser;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  WebBrowser1.Navigate('http://pastebin.com/raw.php?i=4Gcssd8x');
end;

procedure ExecuteJavaScript(WebBrowser: TWebBrowser; const Script: WideString);
var
  HTMLWindow: IHTMLWindow2;
  HTMLDocument: IHTMLDocument2;
begin
  if Supports(WebBrowser.Document, IID_IHTMLDocument2, HTMLDocument) then
  begin
    HTMLWindow := HTMLDocument.parentWindow;
    if Assigned(HTMLWindow) then
    try
      HTMLWindow.execScript(Script, 'JavaScript');
    except
      on E: Exception do
        ShowMessage(Script + sLineBreak + E.Message);
    end;
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  // shift by 250 pixels to top & left
  ExecuteJavaScript(WebBrowser1, Format('moveByPixel(%d, %d)', [-250, -250]));
end;

end.