Don't paint selections in <mask>s, <clipPath>s and <pattern>s

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

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/SVGInlineTextBoxPainter.h"
 
 #include "core/editing/Editor.h"
 #include "core/editing/markers/DocumentMarkerController.h"
 #include "core/editing/markers/RenderedDocumentMarker.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 19 matching lines @@
 static inline bool textShouldBePainted(
     const LayoutSVGInlineText& textLayoutObject) {
   // Font::pixelSize(), returns FontDescription::computedPixelSize(), which
   // returns "int(x + 0.5)".  If the absolute font size on screen is below
   // x=0.5, don't render anything.
   return textLayoutObject.scaledFont().getFontDescription().computedPixelSize();
 }
 
 bool SVGInlineTextBoxPainter::shouldPaintSelection(
     const PaintInfo& paintInfo) const {
-  return !paintInfo.isPrinting() &&
-         m_svgInlineTextBox.getSelectionState() != SelectionNone;
+  // Don't paint selections when printing.
+  if (paintInfo.isPrinting())
+    return false;
+  // Don't paint selections when rendering a mask, clip-path (as a mask),
+  // pattern or feImage (element reference.)
+  if (paintInfo.isRenderingResourceSubtree())
+    return false;
+  return m_svgInlineTextBox.getSelectionState() != SelectionNone;
 }
 
 static bool hasShadow(const PaintInfo& paintInfo, const ComputedStyle& style) {
   // Text shadows are disabled when printing. http://crbug.com/258321
   return style.textShadow() && !paintInfo.isPrinting();
 }
 
 FloatRect SVGInlineTextBoxPainter::boundsForDrawingRecorder(
     const PaintInfo& paintInfo,
     const ComputedStyle& style,
@@ skipping 593 matching lines @@
     }
     FloatRect fragmentRect = m_svgInlineTextBox.selectionRectForTextFragment(
         fragment, textMatchInfo.startPosition, textMatchInfo.endPosition,
         style);
     paintInfo.context.setFillColor(color);
     paintInfo.context.fillRect(fragmentRect);
   }
 }
 
 }  // namespace blink