Underline Thickness is not uniform

Source/core/rendering/InlineFlowBox.cpp

Index: Source/core/rendering/InlineFlowBox.cpp
diff --git a/Source/core/rendering/InlineFlowBox.cpp b/Source/core/rendering/InlineFlowBox.cpp
index b1814adbde2b702cb8ea74996232465335de648e..c849627cf79e22ead24109aee959c857a389c315 100644
--- a/Source/core/rendering/InlineFlowBox.cpp
+++ b/Source/core/rendering/InlineFlowBox.cpp
@@ -1133,11 +1133,63 @@ void InlineFlowBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset,
     childInfo.phase = paintPhase;
     childInfo.updatePaintingRootForChildren(&renderer());
 
-    // Paint our children.
+    float decorationThickness = 0;
+    float finalThickness = 0;
+    float maxDecorationThickness = 0;
+    float minDecorationThickness = 65536.0f;
+
+    // Paint our childrens and calculate underline thickness
     if (paintPhase != PaintPhaseSelfOutline) {
+        InlineBox * start = 0;
+        InlineBox * end = 0;
+
         for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
-            if (curr->renderer().isText() || !curr->boxModelObject()->hasSelfPaintingLayer())
+            if (curr->renderer().isText() || !curr->boxModelObject()->hasSelfPaintingLayer()) {
                 curr->paint(childInfo, paintOffset, lineTop, lineBottom);
+                curr->getPaintDecorationSyle(childInfo, paintOffset, &decorationThickness);
+                if (decorationThickness) {
+                    if (maxDecorationThickness < decorationThickness)
+                        maxDecorationThickness = decorationThickness;
+
+                    if (minDecorationThickness > decorationThickness)
+                        minDecorationThickness = decorationThickness;
+
+                    if (!start)
+                        start = curr;
+                    end = curr;
+                } else if (end != start) {
+                    // found node where decoration style is not applied, ie; normal text node
+                    // lets apply uniform underline from start to end Text Nodes
+                    // We have underline thickness now, let draw it
+                    end = end->nextOnLine();
+                    finalThickness = (minDecorationThickness + maxDecorationThickness) / 2.0f;
+                    for (InlineBox* curr1 = start; curr1 != end; curr1 = curr1->nextOnLine())
+                        curr1->paintDecorationStyle(childInfo, paintOffset, lineTop, lineBottom, finalThickness);
+
+                    finalThickness = 0;
+                    maxDecorationThickness = 0;
+                    minDecorationThickness = 65536.0f;
+                    start = end = 0;
+                } else if ((decorationThickness) && (end == start)) {
+                    start->paintDecorationStyle(childInfo, paintOffset, lineTop, lineBottom, finalThickness);
+                    finalThickness = 0;
+                    maxDecorationThickness = 0;
+                    minDecorationThickness = 65536.0f;
+                    start = end = 0;
+                }
+            }
+        }
+
+        if (start && end) {
+            end = end->nextOnLine();
+            finalThickness = (minDecorationThickness + maxDecorationThickness) / 2.0f;
+            for (InlineBox* curr1 = start; curr1 != end; curr1 = curr1->nextOnLine())
+                curr1->paintDecorationStyle(childInfo, paintOffset, lineTop, lineBottom, finalThickness);
+
+            finalThickness = 0;
+            maxDecorationThickness = 0;
+            minDecorationThickness = 65536.0f;
+            start = end = 0;
         }
     }
 }