Return Optional<float> from SVGSVGElement::Intrinsic{Width,Height}

This provides a more succinct way to express a potentially missing
value, and allows dropping the separate HasIntrinsic{Width,Height}.

For the usage in SVGSVGElement::CurrentViewBoxRect, just drop the use of
IntrinsicWidth/Height() since we resolve percentages against the current
viewport - which matches what a plain SVGLengthContext resolve does in
this case.

Change-Id: I0f6b36e4f34e3ef42adc374100d6a82647301c57
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2509853Reviewed-by: Stephen Chenney <schenney@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#822661}

third_party/blink/renderer/core/layout/svg/layout_svg_root.cc

@@ -62,12 +62,8 @@ LayoutSVGRoot::LayoutSVGRoot(SVGElement* node)
   auto* svg = To<SVGSVGElement>(node);
   DCHECK(svg);
 
-  LayoutSize intrinsic_size(svg->IntrinsicWidth(), svg->IntrinsicHeight());
-  if (!svg->HasIntrinsicWidth())
-    intrinsic_size.SetWidth(LayoutUnit(kDefaultWidth));
-  if (!svg->HasIntrinsicHeight())
-    intrinsic_size.SetHeight(LayoutUnit(kDefaultHeight));
-  SetIntrinsicSize(intrinsic_size);
+  SetIntrinsicSize(LayoutSize(svg->IntrinsicWidth().value_or(kDefaultWidth),
+                              svg->IntrinsicHeight().value_or(kDefaultHeight)));
 }
 
 LayoutSVGRoot::~LayoutSVGRoot() = default;
@@ -80,10 +76,12 @@ void LayoutSVGRoot::UnscaledIntrinsicSizingInfo(
   auto* svg = To<SVGSVGElement>(GetNode());
   DCHECK(svg);
 
+  base::Optional<float> intrinsic_width = svg->IntrinsicWidth();
+  base::Optional<float> intrinsic_height = svg->IntrinsicHeight();
   intrinsic_sizing_info.size =
-      FloatSize(svg->IntrinsicWidth(), svg->IntrinsicHeight());
-  intrinsic_sizing_info.has_width = svg->HasIntrinsicWidth();
-  intrinsic_sizing_info.has_height = svg->HasIntrinsicHeight();
+      FloatSize(intrinsic_width.value_or(0), intrinsic_height.value_or(0));
+  intrinsic_sizing_info.has_width = intrinsic_width.has_value();
+  intrinsic_sizing_info.has_height = intrinsic_height.has_value();
 
   if (!intrinsic_sizing_info.size.IsEmpty()) {
     intrinsic_sizing_info.aspect_ratio = intrinsic_sizing_info.size;

third_party/blink/renderer/core/svg/svg_svg_element.cc

@@ -593,15 +593,10 @@ FloatRect SVGSVGElement::CurrentViewBoxRect() const {
 
   // If no viewBox is specified but non-relative width/height values, then we
   // should always synthesize a viewBox if we're embedded through a SVGImage.
-  FloatSize synthesized_view_box_size(IntrinsicWidth(), IntrinsicHeight());
-  if (!HasIntrinsicWidth())
-    synthesized_view_box_size.SetWidth(
-        width()->CurrentValue()->ScaleByPercentage(
-            CurrentViewportSize().Width()));
-  if (!HasIntrinsicHeight())
-    synthesized_view_box_size.SetHeight(
-        height()->CurrentValue()->ScaleByPercentage(
-            CurrentViewportSize().Height()));
+  SVGLengthContext length_context(this);
+  FloatSize synthesized_view_box_size(
+      width()->CurrentValue()->Value(length_context),
+      height()->CurrentValue()->Value(length_context));
   return FloatRect(FloatPoint(), synthesized_view_box_size);
 }
 
@@ -637,34 +632,26 @@ FloatSize SVGSVGElement::CurrentViewportSize() const {
   return viewport_rect.Size();
 }
 
-bool SVGSVGElement::HasIntrinsicWidth() const {
+base::Optional<float> SVGSVGElement::IntrinsicWidth() const {
+  const SVGLength& width_attr = *width()->CurrentValue();
   // TODO(crbug.com/979895): This is the result of a refactoring, which might
   // have revealed an existing bug that we are not handling math functions
   // involving percentages correctly. Fix it if necessary.
-  return !width()->CurrentValue()->IsPercentage();
+  if (width_attr.IsPercentage())
+    return base::nullopt;
+  SVGLengthContext length_context(this);
+  return width_attr.Value(length_context);
 }
 
-bool SVGSVGElement::HasIntrinsicHeight() const {
+base::Optional<float> SVGSVGElement::IntrinsicHeight() const {
+  const SVGLength& height_attr = *height()->CurrentValue();
   // TODO(crbug.com/979895): This is the result of a refactoring, which might
   // have revealed an existing bug that we are not handling math functions
   // involving percentages correctly. Fix it if necessary.
-  return !height()->CurrentValue()->IsPercentage();
-}
-
-float SVGSVGElement::IntrinsicWidth() const {
-  if (!HasIntrinsicWidth())
-    return 0;
-
-  SVGLengthContext length_context(this);
-  return width()->CurrentValue()->Value(length_context);
-}
-
-float SVGSVGElement::IntrinsicHeight() const {
-  if (!HasIntrinsicHeight())
-    return 0;
-
+  if (height_attr.IsPercentage())
+    return base::nullopt;
   SVGLengthContext length_context(this);
-  return height()->CurrentValue()->Value(length_context);
+  return height_attr.Value(length_context);
 }
 
 AffineTransform SVGSVGElement::ViewBoxToViewTransform(

third_party/blink/renderer/core/svg/svg_svg_element.h

@@ -48,8 +48,8 @@ class SVGSVGElement final : public SVGGraphicsElement,
  public:
   explicit SVGSVGElement(Document&);
 
-  float IntrinsicWidth() const;
-  float IntrinsicHeight() const;
+  base::Optional<float> IntrinsicWidth() const;
+  base::Optional<float> IntrinsicHeight() const;
   FloatSize CurrentViewportSize() const;
   FloatRect CurrentViewBoxRect() const;
   const SVGPreserveAspectRatio* CurrentPreserveAspectRatio() const;
@@ -99,9 +99,6 @@ class SVGSVGElement final : public SVGGraphicsElement,
                         Element* anchor_node);
   bool ZoomAndPanEnabled() const;
 
-  bool HasIntrinsicWidth() const;
-  bool HasIntrinsicHeight() const;
-
   SVGAnimatedLength* x() const { return x_.Get(); }
   SVGAnimatedLength* y() const { return y_.Get(); }
   SVGAnimatedLength* width() const { return width_.Get(); }