Clean up single namespace forward-declarations

Done using the following ruby script:

Dir.glob('**/*.h').each { |file|
  if File.file?(file)
    s = File.read(file)
    t = s.gsub(/^namespace .+ \{\n\s*class .*;\n\s*\}.*$/) { |m| m.gsub(/\n\s*/, ' ').gsub(/\s*\/\/.*$/, '') }
    if t != s
      puts file
      File.open(file, 'w').write(t)
    end
  end
}

Change-Id: Iffcb966e90eb8e1a625eccd5dd0b94f000ae368e
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/qmakeprojectmanager/customwidgetwizard/customwidgetpluginwizardpage.h

@@ -41,9 +41,7 @@ namespace Internal {
 struct PluginOptions;
 class CustomWidgetWidgetsWizardPage;
 
-namespace Ui {
-    class CustomWidgetPluginWizardPage;
-}
+namespace Ui { class CustomWidgetPluginWizardPage; }
 
 class CustomWidgetPluginWizardPage : public QWizardPage
 {

src/plugins/qmakeprojectmanager/customwidgetwizard/customwidgetwidgetswizardpage.h

@@ -46,9 +46,7 @@ namespace Internal {
 class ClassDefinition;
 struct PluginOptions;
 
-namespace Ui {
-    class CustomWidgetWidgetsWizardPage;
-}
+namespace Ui { class CustomWidgetWidgetsWizardPage; }
 
 class CustomWidgetWidgetsWizardPage : public QWizardPage
 {

src/plugins/qmakeprojectmanager/customwidgetwizard/plugingenerator.h

@@ -39,9 +39,7 @@ QT_BEGIN_NAMESPACE
 class QWidget;
 QT_END_NAMESPACE
 
-namespace Core {
-    class GeneratedFile;
-}
+namespace Core { class GeneratedFile; }
 
 namespace QmakeProjectManager {
 namespace Internal {