[Line Layout API] Some harder SVGTextLayoutEngine changes

third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp

Index: third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp
diff --git a/third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp b/third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp
index 7d44ebb130e1be97065a02cb9979dcc48c801c58..627aae9435e73412af1b30fb59df5c25c0d24ce8 100644
--- a/third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp
+++ b/third_party/WebKit/Source/core/layout/svg/SVGTextLayoutEngine.cpp
@@ -171,8 +171,13 @@ void SVGTextLayoutEngine::beginTextPathLayout(SVGInlineFlowBox* flowBox)
     lineLayout.layoutCharactersInTextBoxes(flowBox);
 
     m_inPathLayout = true;
+    // Do we need to add a LineLayoutSVGTextPath class to handle this logic?
+    // I'd imagine it'd only have 2 methods, startOffset() and layoutPath().
     LayoutSVGTextPath* textPath = &toLayoutSVGTextPath(flowBox->layoutObject());
 
+    // Actually, what would I do with Path here? Would we have to add a LineLayoutPath
+    // class too? And then what would we do about PositionCalculator?
+    // Does this pattern bring to mind any examples I can look at?
     Path path = textPath->layoutPath();
     if (path.isEmpty())
         return;
@@ -192,7 +197,7 @@ void SVGTextLayoutEngine::beginTextPathLayout(SVGInlineFlowBox* flowBox)
     SVGLengthAdjustType lengthAdjust = SVGLengthAdjustUnknown;
     float desiredTextLength = 0;
 
-    if (SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromLayoutObject(textPath)) {
+    if (SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromLayoutObject(flowBox->lineLayoutItem())) {
         SVGLengthContext lengthContext(textContentElement);
         lengthAdjust = textContentElement->lengthAdjust()->currentValue()->enumValue();
         if (textContentElement->textLengthIsSpecifiedByUser())
@@ -246,7 +251,7 @@ void SVGTextLayoutEngine::layoutInlineTextBox(SVGInlineTextBox* textBox)
 
 static bool definesTextLengthWithSpacing(const InlineFlowBox* start)
 {
-    SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromLayoutObject(&start->layoutObject());
+    SVGTextContentElement* textContentElement = SVGTextContentElement::elementFromLayoutObject(start->lineLayoutItem());
     return textContentElement
         && textContentElement->lengthAdjust()->currentValue()->enumValue() == SVGLengthAdjustSpacing
         && textContentElement->textLengthIsSpecifiedByUser();