Convert some call sites to use explicit LayoutRect->FloatRect conversion.

Source/core/layout/svg/LayoutSVGText.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) Research In Motion Limited 2010-2012. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 57 matching lines @@
     PositionWithAffinity positionForPoint(const LayoutPoint&) override;
 
     void layout() override;
 
     void absoluteQuads(Vector<FloatQuad>&, bool* wasFixed) const override;
 
     void addChild(LayoutObject* child, LayoutObject* beforeChild = nullptr) override;
     void removeChild(LayoutObject*) override;
     void willBeDestroyed() override;
 
-    FloatRect objectBoundingBox() const override { return frameRect(); }
+    FloatRect objectBoundingBox() const override { return FloatRect(frameRect()); }
     FloatRect strokeBoundingBox() const override;
 
     RootInlineBox* createRootInlineBox() override;
 
     bool shouldHandleSubtreeMutations() const;
 
     bool m_needsReordering : 1;
     bool m_needsPositioningValuesUpdate : 1;
     bool m_needsTransformUpdate : 1;
     bool m_needsTextMetricsUpdate : 1;
     SVGTextLayoutAttributesBuilder m_layoutAttributesBuilder;
     Vector<SVGTextLayoutAttributes*> m_layoutAttributes;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutSVGText, isSVGText());
 
 }
 
 #endif