[IFC][Subpixel] Do not use integral FontMetrics APIs in RenderInline:…

…:baselinePosition

https://bugs.webkit.org/show_bug.cgi?id=270421

Reviewed by Antti Koivisto.

This is in preparation for removing integral (vertical) pixel snapping.

* Source/WebCore/rendering/RenderInline.cpp:
(WebCore::RenderInline::baselinePosition const):

Canonical link: https://commits.webkit.org/275623@main

Source/WebCore/rendering/RenderInline.cpp

@@ -891,9 +891,9 @@ LayoutUnit RenderInline::lineHeight(bool firstLine, LineDirectionMode /*directio
 
 LayoutUnit RenderInline::baselinePosition(FontBaseline baselineType, bool firstLine, LineDirectionMode direction, LinePositionMode linePositionMode) const
 {
-    const RenderStyle& style = firstLine ? firstLineStyle() : this->style();
-    const FontMetrics& fontMetrics = style.metricsOfPrimaryFont();
-    return LayoutUnit { (fontMetrics.intAscent(baselineType) + (lineHeight(firstLine, direction, linePositionMode) - fontMetrics.intHeight()) / 2).toInt() };
+    auto& style = firstLine ? firstLineStyle() : this->style();
+    auto& fontMetrics = style.metricsOfPrimaryFont();
+    return LayoutUnit { fontMetrics.ascent(baselineType) + (lineHeight(firstLine, direction, linePositionMode) - fontMetrics.height()) / 2 };
 }
 
 LayoutSize RenderInline::offsetForInFlowPositionedInline(const RenderBox* child) const