Port deprecated QLayout::margin call

As the method impl suggests, the left value is preferred if all the values are the same.
This is the case for the given layout.

```cpp
int QLayout::margin() const
{
    int left, top, right, bottom;
    getContentsMargins(&left, &top, &right, &bottom);
    if (left == top && top == right && right == bottom) {
        return left;
    } else {
        return -1;
    }
}
```

1 files changed, 1 insertions, 1 deletions

diff --git a/src/views/tooltips/dolphinfilemetadatawidget.cpp b/src/views/tooltips/dolphinfilemetadatawidget.cpp
index b147135bf..e914593fb 100644
--- a/src/views/tooltips/dolphinfilemetadatawidget.cpp
+++ b/src/views/tooltips/dolphinfilemetadatawidget.cpp
@@ -66,7 +66,7 @@ DolphinFileMetaDataWidget::DolphinFileMetaDataWidget(QWidget* parent) :
 
     QHBoxLayout* layout = new QHBoxLayout(this);
     layout->addWidget(m_preview);
-    layout->addSpacing(layout->margin());
+    layout->addSpacing(layout->contentsMargins().left());
     layout->addLayout(textLayout);
 }