Include glyph overflow in SVG text bounding boxes

third_party/WebKit/Source/core/layout/line/GlyphOverflow.h

Index: third_party/WebKit/Source/core/layout/line/GlyphOverflow.h
diff --git a/third_party/WebKit/Source/core/layout/line/GlyphOverflow.h b/third_party/WebKit/Source/core/layout/line/GlyphOverflow.h
index f13382f1327e7e476c88e6c15ee4440be7134370..6b70e03daa67acd37cd24943b66f410e12fc5dc8 100644
--- a/third_party/WebKit/Source/core/layout/line/GlyphOverflow.h
+++ b/third_party/WebKit/Source/core/layout/line/GlyphOverflow.h
@@ -46,12 +46,31 @@ struct GlyphOverflow {
         return !left && !right && !top && !bottom;
     }
 
+    // These helper functions are exposed to share logic with SVG which computes overflow
+    // in floating point (see: SVGTextLayoutEngine).
+    static float topOverflow(const FloatRect& bounds, float ascent)
+    {
+        return std::max(0.0f, -bounds.y() - ascent);
+    }
+    static float bottomOverflow(const FloatRect& bounds, float descent)
+    {
+        return std::max(0.0f, bounds.maxY() - descent);
+    }
+    static float leftOverflow(const FloatRect& bounds)
+    {
+        return std::max(0.0f, -bounds.x());
+    }
+    static float rightOverflow(const FloatRect& bounds, float textWidth)
+    {
+        return std::max(0.0f, bounds.maxX() - textWidth);
+    }
+
     void setFromBounds(const FloatRect& bounds, float ascent, float descent, float textWidth)
     {
-        top = ceilf(std::max(0.0f, -bounds.y() - ascent));
-        bottom = ceilf(std::max(0.0f, bounds.maxY() - descent));
-        left = ceilf(std::max(0.0f, -bounds.x()));
-        right = ceilf(std::max(0.0f, bounds.maxX() - textWidth));
+        top = ceilf(topOverflow(bounds, ascent));
+        bottom = ceilf(bottomOverflow(bounds, descent));
+        left = ceilf(leftOverflow(bounds));
+        right = ceilf(rightOverflow(bounds, textWidth));
     }
 
     // Top and bottom are the amounts of glyph overflows exceeding the font metrics' ascent and descent, respectively.