Add image-rendering: pixelated.

Source/devtools/front_end/cm/css.js

 CodeMirror.defineMode("css", function(config, parserConfig) {
   "use strict";
 
   if (!parserConfig.propertyKeywords) parserConfig = CodeMirror.resolveMode("text/css");
 
   var indentUnit = config.indentUnit || config.tabSize || 2,
       hooks = parserConfig.hooks || {},
       atMediaTypes = parserConfig.atMediaTypes || {},
       atMediaFeatures = parserConfig.atMediaFeatures || {},
       propertyKeywords = parserConfig.propertyKeywords || {},
@@ skipping 493 matching lines @@
     "media-sliderthumb", "media-time-remaining-display", "media-volume-slider",
     "media-volume-slider-container", "media-volume-sliderthumb", "medium",
     "menu", "menulist", "menulist-button", "menulist-text",
     "menulist-textfield", "menutext", "message-box", "middle", "min-intrinsic",
     "mix", "mongolian", "monospace", "move", "multiple", "myanmar", "n-resize",
     "narrower", "ne-resize", "nesw-resize", "no-close-quote", "no-drop",
     "no-open-quote", "no-repeat", "none", "normal", "not-allowed", "nowrap",
     "ns-resize", "nw-resize", "nwse-resize", "oblique", "octal", "open-quote",
     "optimizeLegibility", "optimizeSpeed", "oriya", "oromo", "outset",
     "outside", "outside-shape", "overlay", "overline", "padding", "padding-box",
-    "painted", "page", "paused", "persian", "plus-darker", "plus-lighter", "pointer",
+    "painted", "page", "paused", "persian", "pixelated","plus-darker", "plus-lighter", "pointer",
     "polygon", "portrait", "pre", "pre-line", "pre-wrap", "preserve-3d", "progress", "push-button",
     "radio", "read-only", "read-write", "read-write-plaintext-only", "rectangle", "region",
     "relative", "repeat", "repeat-x", "repeat-y", "reset", "reverse", "rgb", "rgba",
     "ridge", "right", "round", "row-resize", "rtl", "run-in", "running",
     "s-resize", "sans-serif", "scroll", "scrollbar", "se-resize", "searchfield",
     "searchfield-cancel-button", "searchfield-decoration",
     "searchfield-results-button", "searchfield-results-decoration",
     "semi-condensed", "semi-expanded", "separate", "serif", "show", "sidama",
     "single", "skip-white-space", "slide", "slider-horizontal",
     "slider-vertical", "sliderthumb-horizontal", "sliderthumb-vertical", "slow",
@@ skipping 105 matching lines @@
           return ["operator", "interpolation"];
         } else {
           stream.eatWhile(/[\w\\\-]/);
           return ["atom", "hash"];
         }
       }
     },
     name: "css"
   });
 })();