LibGUI: Consider TextEditor icon size when scrolling text horizontally

If an icon exists and the horizontal scroll value is larger than 0,
translate the TextEditor painter by the icon size and padding.

The text would scroll over the icon when the text was long enough to
trigger a horizontal scroll.

Fixes #13669.

Userland/Libraries/LibGUI/TextEditor.cpp

@@ -452,7 +452,10 @@ void TextEditor::paint_event(PaintEvent& event)
         painter.draw_line(ruler_rect.top_right(), ruler_rect.bottom_right(), palette().ruler_border());
     }
 
-    painter.translate(-horizontal_scrollbar().value(), -vertical_scrollbar().value());
+    auto horizontal_scrollbar_value = horizontal_scrollbar().value();
+    painter.translate(-horizontal_scrollbar_value, -vertical_scrollbar().value());
+    if (m_icon && horizontal_scrollbar_value > 0)
+        painter.translate(min(icon_size() + icon_padding(), horizontal_scrollbar_value), 0);
     painter.translate(gutter_width(), 0);
     painter.translate(ruler_width(), 0);