Calculate correct cull rect for SVG inline text boxes.

third_party/WebKit/Source/core/paint/SVGInlineTextBoxPainter.cpp

Index: third_party/WebKit/Source/core/paint/SVGInlineTextBoxPainter.cpp
diff --git a/third_party/WebKit/Source/core/paint/SVGInlineTextBoxPainter.cpp b/third_party/WebKit/Source/core/paint/SVGInlineTextBoxPainter.cpp
index 71497f19b4e7d726b137fc59243de4674977f0d5..0f588d7151fa36e4b4dbf9ae893fa8142aa0eb11 100644
--- a/third_party/WebKit/Source/core/paint/SVGInlineTextBoxPainter.cpp
+++ b/third_party/WebKit/Source/core/paint/SVGInlineTextBoxPainter.cpp
@@ -45,13 +45,12 @@ FloatRect SVGInlineTextBoxPainter::boundsForDrawingRecorder(
     // computation in SVGInlineTextBox::calculateBoundaries, and the fact that vertical (etc)
     // layouts are handled by SVGTextLayoutEngine.
     LayoutRect bounds(
-        m_svgInlineTextBox.topLeft(),
+        LayoutPoint(m_svgInlineTextBox.topLeft() + paintOffset),
         LayoutSize(m_svgInlineTextBox.logicalWidth(), m_svgInlineTextBox.logicalHeight()));
     if (includeSelectionRect) {

[pdr., 2016/07/11 18:41:09]

I looked into this and it turns out that the code is not needed.
includeSelectionRect is poorly named and should be called
includeSelectionRectForMarkers. It turns out that the marker code only paints
within the bounds above, so this code isn't useful. Refactoring this to be
correct (i.e., still work if the marker bounds change in the future) seems very
hard though :( I couldn't think of a way to test this directly.

[wkorman, 2016/07/12 22:38:05]

Discussed in person briefly, it still seemed worth fixing the current broken
unnecessarily-large cull rect and thought was a unit test could work out.

         bounds.unite(m_svgInlineTextBox.localSelectionRect(
             m_svgInlineTextBox.start(), m_svgInlineTextBox.start() + m_svgInlineTextBox.len()));
     }
-    bounds.moveBy(paintOffset);
     return FloatRect(bounds);
 }