2269:
2271
2272
2273
2274
Merge branch 'v1.7perf' into v1.7.2264.3

Conflicts:
	Source/HtmlRenderer.WinFormControls/Platform/HtmlContainerImpl.cs
	Source/HtmlRenderer/1_Boxes/1_BoxCore/CssLineBox.cs
	Source/HtmlRenderer/1_Boxes/4_Render/BordersDrawHandler.cs
	Source/HtmlRenderer/1_Boxes/6_OtherBoxes/ListItemHelper.cs
	Source/HtmlRenderer/BridgesAndBuilder/ContentTextSplitter.cs
	Source/HtmlRenderer/BridgesAndBuilder/RunListCreator.cs