Add support for the object-fit CSS property.

Source/core/rendering/RenderReplaced.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011-2012. 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 293 matching lines @@
     // function was added, since all it has done is make the code more unclear.
     constrainedSize = intrinsicSize;
     if (intrinsicRatio && !isPercentageIntrinsicSize && !intrinsicSize.isEmpty() && style()->logicalWidth().isAuto() && style()->logicalHeight().isAuto()) {
         // We can't multiply or divide by 'intrinsicRatio' here, it breaks tests, like fast/images/zoomed-img-size.html, which
         // can only be fixed once subpixel precision is available for things like intrinsicWidth/Height - which include zoom!
         constrainedSize.setWidth(RenderBox::computeReplacedLogicalHeight() * intrinsicSize.width() / intrinsicSize.height());
         constrainedSize.setHeight(RenderBox::computeReplacedLogicalWidth() * intrinsicSize.height() / intrinsicSize.width());
     }
 }
 
+LayoutRect RenderReplaced::replacedContentRect(const LayoutSize* overriddenIntrinsicSize) const

[ojan, 2013/08/09 23:27:26]

I don't think we typically use pointers to LayoutSizes. This should be "const
LayoutSize&".

[mstensho (USE GERRIT), 2013/08/12 13:39:11]

But it's an optional parameter, currently only specified by RenderVideo. Or do
you think it would it be better to pass a zero LayoutSize object in the other
cases, although that's more expensive?

[ojan, 2013/08/12 17:25:57]

Ah right. Nevermind. What you have here is fine.

+{
+    LayoutRect contentRect = contentBoxRect();
+    EObjectFit objectFit = style()->objectFit();
+    if (objectFit == ObjectFitFill)
+        return contentRect;
+
+    LayoutSize intrinsicSize = overriddenIntrinsicSize ? *overriddenIntrinsicSize : this->intrinsicSize();
+    if (!intrinsicSize.width() || !intrinsicSize.height())
+        return contentRect;
+
+    LayoutRect finalRect = contentRect;
+    switch (objectFit) {
+    case ObjectFitContain:
+    case ObjectFitScaleDown:
+    case ObjectFitCover:
+        finalRect.setSize(finalRect.size().fitToAspectRatio(intrinsicSize, objectFit == ObjectFitCover ? AspectRatioFitGrow : AspectRatioFitShrink));
+        if (objectFit != ObjectFitScaleDown || finalRect.width() <= intrinsicSize.width())
+            break;
+        // fall through
+    case ObjectFitNone:
+        finalRect.setSize(intrinsicSize);
+        break;
+    case ObjectFitFill:
+        ASSERT_NOT_REACHED();
+    }
+
+    // This is where object-position should be taken into account, but since it's not implemented

[ojan, 2013/08/09 23:27:26]

This should be:
// FIXME: This is where...

[mstensho (USE GERRIT), 2013/08/12 13:39:11]

Done.

+    // yet, assume the initial value of "50% 50%".
+    LayoutUnit xOffset = (contentRect.width() - finalRect.width()) / 2;
+    LayoutUnit yOffset = (contentRect.height() - finalRect.height()) / 2;
+    finalRect.move(xOffset, yOffset);
+
+    return finalRect;
+}
+
 void RenderReplaced::computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio, bool& isPercentageIntrinsicSize) const
 {
     // If there's an embeddedContentBox() of a remote, referenced document available, this code-path should never be used.
     ASSERT(!embeddedContentBox());
     isPercentageIntrinsicSize = false;
     intrinsicSize = FloatSize(intrinsicLogicalWidth(), intrinsicLogicalHeight());
 
     // Figure out if we need to compute an intrinsic ratio.
     if (intrinsicSize.isEmpty() || !rendererHasAspectRatio(this))
         return;
@@ skipping 250 matching lines @@
 
     if (style()) {
         if (v)
             r.inflate(style()->outlineSize());
     }
     computeRectForRepaint(repaintContainer, r);
     return r;
 }
 
 }