[turbolizer] Enlarge node labels and bubbles. Fix dead node display on old JSON.

tools/turbolizer/edge.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var MINIMUM_EDGE_SEPARATION = 20;
 
 function isEdgeInitiallyVisible(target, index, source, type) {
   return type == "control" && (target.cfg || source.cfg);
 }
 
@@ skipping 31 matching lines @@
     return (target.x < source.x)
       ? (target.x + target.getTotalNodeWidth() + inputOffset)
       : (target.x - inputOffset)
   }
 }
 
 Edge.prototype.generatePath = function(graph) {
   var target = this.target;
   var source = this.source;
   var input_x = target.x + target.getInputX(this.index);
+  var arrowheadHeight = 7;
+  var input_y = target.y - 2 * DEFAULT_NODE_BUBBLE_RADIUS - arrowheadHeight;
   var output_x = source.x + source.getOutputX();
-  var output_y = source.y + DEFAULT_NODE_HEIGHT + DEFAULT_NODE_BUBBLE_RADIUS;
+  var output_y = source.y + graph.getNodeHeight(source) + DEFAULT_NODE_BUBBLE_RADIUS;
   var inputApproach = target.getInputApproach(this.index);
   var outputApproach = source.getOutputApproach(graph);
   var horizontalPos = this.getInputHorizontalPosition(graph);
 
   var result = "M" + output_x + "," + output_y +
     "L" + output_x + "," + outputApproach +
     "L" + horizontalPos + "," + outputApproach;
 
   if (horizontalPos != input_x) {
     result += "L" + horizontalPos + "," + inputApproach;
   } else {
     if (inputApproach < outputApproach) {
       inputApproach = outputApproach;
     }
   }
 
   result += "L" + input_x + "," + inputApproach +
-    "L" + input_x + "," + (target.y - DEFAULT_NODE_BUBBLE_RADIUS - 12);
+    "L" + input_x + "," + input_y;
   return result;
 }
 
 Edge.prototype.isBackEdge = function() {
   return this.target.hasBackEdges() && (this.target.rank < this.source.rank);
 }