Add filtering by priority in the Network filter area.

third_party/WebKit/Source/devtools/front_end/network/NetworkDataGridNode.js

Index: third_party/WebKit/Source/devtools/front_end/network/NetworkDataGridNode.js
diff --git a/third_party/WebKit/Source/devtools/front_end/network/NetworkDataGridNode.js b/third_party/WebKit/Source/devtools/front_end/network/NetworkDataGridNode.js
index 57690c4b8faf3d657b5b53792b813e71163e4c17..0702b205850603d6073452dcfaca2f7562fde031 100644
--- a/third_party/WebKit/Source/devtools/front_end/network/NetworkDataGridNode.js
+++ b/third_party/WebKit/Source/devtools/front_end/network/NetworkDataGridNode.js
@@ -224,6 +224,7 @@ Network.NetworkRequestNode = class extends Network.NetworkNode {
     return (aScore - bScore) || aRequest.indentityCompare(bRequest);
   }
 
+  // TODO(allada) This function deserves to be in a network-common of some sort.
   /**
    * @param {!Network.NetworkNode} a
    * @param {!Network.NetworkNode} b
@@ -235,16 +236,7 @@ Network.NetworkRequestNode = class extends Network.NetworkNode {
     var bRequest = b.request();
     if (!aRequest || !bRequest)
       return !aRequest ? -1 : 1;
-    var priorityMap = Network.NetworkRequestNode._symbolicToNumericPriority;
-    if (!priorityMap) {
-      Network.NetworkRequestNode._symbolicToNumericPriority = new Map();
-      priorityMap = Network.NetworkRequestNode._symbolicToNumericPriority;
-      priorityMap.set(Protocol.Network.ResourcePriority.VeryLow, 1);
-      priorityMap.set(Protocol.Network.ResourcePriority.Low, 2);
-      priorityMap.set(Protocol.Network.ResourcePriority.Medium, 3);
-      priorityMap.set(Protocol.Network.ResourcePriority.High, 4);
-      priorityMap.set(Protocol.Network.ResourcePriority.VeryHigh, 5);
-    }
+    var priorityMap = Components.prioritySymbolToNumericMap();
     var aScore = priorityMap.get(aRequest.initialPriority()) || 0;

[allada, 2016/12/22 23:57:24]

Try:

var aPriority = aRequest.initialPriority();
var aScore = aPriority ? priorityMap.get(aPriority) : 0;

var bPriority = aRequest.initialPriority();
var bScore = bPriority ? priorityMap.get(bPriority) : 0;

     var bScore = priorityMap.get(bRequest.initialPriority()) || 0;