Calculate Background Image Geometries using sub-pixel values

third_party/WebKit/Source/core/layout/LayoutListMarker.cpp

Index: third_party/WebKit/Source/core/layout/LayoutListMarker.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutListMarker.cpp b/third_party/WebKit/Source/core/layout/LayoutListMarker.cpp
index f36302249cc85002fe72aa753044fa823212404a..49ef363a0f90771b4940dde53ae4101b1d8098fc 100644
--- a/third_party/WebKit/Source/core/layout/LayoutListMarker.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutListMarker.cpp
@@ -65,15 +65,15 @@ LayoutListMarker* LayoutListMarker::createAnonymous(LayoutListItem* item)
     return layoutObject;
 }
 
-IntSize LayoutListMarker::imageBulletSize() const
+LayoutSize LayoutListMarker::imageBulletSize() const
 {
     ASSERT(isImage());
 
     // FIXME: This is a somewhat arbitrary default width. Generated images for markers really won't
     // become particularly useful until we support the CSS3 marker pseudoclass to allow control over
     // the width and height of the marker box.
-    int bulletWidth = style()->fontMetrics().ascent() / 2;
-    IntSize defaultBulletSize(bulletWidth, bulletWidth);
+    LayoutUnit bulletWidth = style()->fontMetrics().ascent() / LayoutUnit(2);
+    LayoutSize defaultBulletSize(bulletWidth, bulletWidth);
     return calculateImageIntrinsicDimensions(m_image.get(), defaultBulletSize, DoNotScaleByEffectiveZoom);
 }
 
@@ -164,7 +164,7 @@ void LayoutListMarker::imageChanged(WrappedImagePtr o, const IntRect*)
     if (o != m_image->data())
         return;
 
-    LayoutSize imageSize = isImage() ? LayoutSize(imageBulletSize()) : LayoutSize();
+    LayoutSize imageSize = isImage() ? imageBulletSize() : LayoutSize();
     if (size() != imageSize || m_image->errorOccurred())
         setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::ImageChanged);
     else
@@ -402,7 +402,7 @@ bool LayoutListMarker::isInside() const
 IntRect LayoutListMarker::getRelativeMarkerRect() const
 {
     if (isImage()) {
-        IntSize imageSize = imageBulletSize();
+        IntSize imageSize = flooredIntSize(imageBulletSize());

[eae, 2015/11/25 00:21:05]

Not pixel snapped?

[leviw_travelin_and_unemployed, 2015/11/25 00:31:56]

Negative. This ends up being far better than the alternative. The old code also
floored all these values or operated on integers.

         return IntRect(0, 0, imageSize.width(), imageSize.height());
     }