Merge 150896 "Dirty the first RootInlineBox, always"

Source/core/rendering/svg/SVGRootInlineBox.cpp

Index: Source/core/rendering/svg/SVGRootInlineBox.cpp
===================================================================
--- Source/core/rendering/svg/SVGRootInlineBox.cpp	(revision 152061)
+++ Source/core/rendering/svg/SVGRootInlineBox.cpp	(working copy)
@@ -68,6 +68,14 @@
     }
 }
 
+void SVGRootInlineBox::markDirty(bool dirty)
+{
+    if (dirty)
+        for (InlineBox* child = firstChild(); child; child = child->nextOnLine())
+            child->markDirty(true);
+    RootInlineBox::markDirty(dirty);
+}
+
 void SVGRootInlineBox::computePerCharacterLayoutInformation()
 {
     RenderSVGText* textRoot = toRenderSVGText(block());