Help: fix forward declaration

Change-Id: I88b5cca65d7e98e7f9d9e5d082cc137e822bc9b4
Reviewed-by: hjk <hjk@qt.io>

src/plugins/help/centralwidget.h

@@ -32,8 +32,6 @@
 namespace Help {
 namespace Internal {
 
-class HelpViewer;
-class PrintHelper;
 
 class CentralWidget : public HelpWidget
 {

src/plugins/help/generalsettingspage.h

@@ -33,7 +33,6 @@
 namespace Help {
 namespace Internal {
 
-class CentralWidget;
 
 class GeneralSettingsPage : public Core::IOptionsPage
 {

src/plugins/help/helpplugin.h

@@ -35,16 +35,11 @@
 #include <QStringList>
 
 QT_BEGIN_NAMESPACE
-class QAction;
-class QMenu;
-class QToolButton;
 class QUrl;
 QT_END_NAMESPACE
 
 namespace Core {
-class MiniSplitter;
 class SideBar;
-class SideBarItem;
 }   // Core
 
 namespace Utils { class StyledBar; }
@@ -54,12 +49,10 @@ namespace Internal {
 class CentralWidget;
 class DocSettingsPage;
 class FilterSettingsPage;
-class GeneralSettingsPage;
 class HelpMode;
 class HelpViewer;
 class LocalHelpManager;
 class OpenPagesManager;
-class SearchWidget;
 class SearchTaskHandler;
 
 class HelpPlugin : public ExtensionSystem::IPlugin

src/plugins/help/helpwidget.h

@@ -33,7 +33,6 @@
 QT_BEGIN_NAMESPACE
 class QAction;
 class QComboBox;
-class QFont;
 class QMenu;
 class QPrinter;
 class QStackedWidget;

src/plugins/help/searchwidget.h

@@ -34,7 +34,6 @@
 QT_BEGIN_NAMESPACE
 class QHelpSearchEngine;
 class QHelpSearchResultWidget;
-class QMouseEvent;
 class QUrl;
 QT_END_NAMESPACE