Merge image sizing algorithms

third_party/WebKit/Source/core/style/StyleImage.cpp

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "core/style/StyleImage.h"
+
+#include "core/svg/graphics/SVGImage.h"
+#include "core/svg/graphics/SVGImageForContainer.h"
+
+namespace blink {
+
+LayoutSize StyleImage::imageSizeForSVGImage(SVGImage* svgImage, float multiplier, const LayoutSize& defaultObjectSize) const
+{
+    FloatSize unzoomedDefaultObjectSize(defaultObjectSize);
+    unzoomedDefaultObjectSize.scale(1 / multiplier);
+    LayoutSize concreteObjectSize(svgImage->calculateConcreteObjectSize(unzoomedDefaultObjectSize));
+
+    // Don't let images that have a width/height >= 1 shrink below 1 when zoomed.
+    LayoutSize minimumSize(concreteObjectSize.width() > LayoutUnit() ? LayoutUnit(1) : LayoutUnit(),
+        concreteObjectSize.height() > LayoutUnit() ? LayoutUnit(1) : LayoutUnit());
+    concreteObjectSize.scale(multiplier);
+    concreteObjectSize.clampToMinimumSize(minimumSize);
+    return concreteObjectSize;
+}
+
+} // namespace blink