DevTools: Handle idle frames on timeline events overview.

Source/devtools/front_end/timeline/TimelineEventOverview.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 255 matching lines @@
         var baseY = (position + height) * window.devicePixelRatio;
         var y = baseY + 10;
         var ctx = this._context;
         ctx.save();
         ctx.beginPath();
         ctx.rect(0, position * window.devicePixelRatio, this._canvas.width, height * window.devicePixelRatio);
         ctx.clip();
         ctx.beginPath();
         ctx.lineWidth = 1 * window.devicePixelRatio;
         ctx.strokeStyle = "hsl(110, 50%, 60%)";
-        ctx.fillStyle = "hsl(110, 50%, 70%)";
+        ctx.fillStyle = "hsl(110, 50%, 80%)";
         ctx.moveTo(0, y);
         for (var i = 0; i < frames.length; ++i) {
             var frame = frames[i];
-            var x = 0.5 + Math.round((frame.startTime - timeOffset) * scale);
+            var x = Math.round((frame.startTime - timeOffset) * scale) + 0.5;
             ctx.lineTo(x, y);
-            y = 0.5 + Math.round(baseY - visualHeight * Math.min(baseFrameDurationMs / frame.duration, 1));
+            y = frame.idle ? baseY + 0.5 : Math.round(baseY - visualHeight * Math.min(baseFrameDurationMs / frame.duration, 1)) - 0.5;
             ctx.lineTo(x, y);
         }
         ctx.lineTo(this._canvas.width, y);
         ctx.lineTo(this._canvas.width, baseY + 10);
         ctx.closePath();
         ctx.stroke();
         ctx.fill();
         ctx.restore();
         return height;
     },
@@ skipping 92 matching lines @@
         for (var g of this._groupError.keys()) {
             if (!g)
                 continue;
             var value = this._groupError.get(g);
             value += (1 - value) * ratio;
             this._groupError.set(g, value);
         }
         return toDistribute;
     }
 }