Replace set[Plain]Text(QString()) with clear()

...where applicable. Shorter, faster, more semantic.

Change-Id: Ifb1cf200f489f62a79e12c761e98a846992744dc
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/coreplugin/actionmanager/commandmappings.cpp

@@ -249,7 +249,7 @@ void CommandMappings::finish()
 void CommandMappings::commandChanged(QTreeWidgetItem *current)
 {
     if (!current || !current->data(0, Qt::UserRole).isValid()) {
-        d->targetEdit->setText(QString());
+        d->targetEdit->clear();
         d->targetEditGroup->setEnabled(false);
         return;
     }

src/plugins/coreplugin/dialogs/externaltoolconfig.cpp

@@ -521,11 +521,11 @@ void ExternalToolConfig::showInfoForItem(const QModelIndex &index)
     updateButtons(index);
     ExternalTool *tool = m_model->toolForIndex(index);
     if (!tool) {
-        ui->description->setText(QString());
+        ui->description->clear();
         ui->executable->setPath(QString());
-        ui->arguments->setText(QString());
+        ui->arguments->clear();
         ui->workingDirectory->setPath(QString());
-        ui->inputText->setPlainText(QString());
+        ui->inputText->clear();
         ui->infoWidget->setEnabled(false);
         return;
     }

src/plugins/coreplugin/dialogs/newdialog.cpp

@@ -429,7 +429,7 @@ void NewDialog::currentItemChanged(const QModelIndex &index)
         }
 
     } else {
-        m_ui->templateDescription->setText(QString());
+        m_ui->templateDescription->clear();
     }
     updateOkButton();
 }

src/plugins/coreplugin/dialogs/settingsdialog.cpp

@@ -512,7 +512,7 @@ void SettingsDialog::currentChanged(const QModelIndex &current)
         showCategory(m_proxyModel->mapToSource(current).row());
     } else {
         m_stackedLayout->setCurrentIndex(0);
-        m_headerLabel->setText(QString());
+        m_headerLabel->clear();
     }
 }
 

src/plugins/coreplugin/generalsettings.cpp

@@ -211,7 +211,7 @@ void GeneralSettings::resetWarnings()
 void GeneralSettings::resetTerminal()
 {
     if (HostOsInfo::isAnyUnixHost())
-        m_page->terminalComboBox->lineEdit()->setText(QString());
+        m_page->terminalComboBox->lineEdit()->clear();
 }
 
 void GeneralSettings::resetFileBrowser()

src/plugins/coreplugin/outputpanemanager.cpp

@@ -751,7 +751,7 @@ void OutputPaneToggleButton::setIconBadgeNumber(int number)
 
         //Do not show yet, we wait until the button has been resized
     } else {
-        m_label->setText(QString());
+        m_label->clear();
         m_label->hide();
     }
     updateGeometry();