Utils: Make TreeViews use setUniformRowHeights by default

When applicable, the flag makes a significant difference in
performacnce. However is easily forgotten in cases where it
is applicable, and cases where it is accidentally used are
easily spotted visually. So arguably, opt-out is a better
default than opt-in.

Change-Id: I88aeb05b42533ba4e23c39573a3ddd016343cd55
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/autotest/testresultspane.cpp

@@ -56,6 +56,7 @@ namespace Internal {
 ResultsTreeView::ResultsTreeView(QWidget *parent)
     : TreeView(parent)
 {
+    setUniformRowHeights(false);
     setAttribute(Qt::WA_MacShowFocusRect, false);
     setFrameStyle(NoFrame);
 }