Add filtering by priority in the Network filter area.

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

Index: third_party/WebKit/Source/devtools/front_end/network/FilterSuggestionBuilder.js
diff --git a/third_party/WebKit/Source/devtools/front_end/network/FilterSuggestionBuilder.js b/third_party/WebKit/Source/devtools/front_end/network/FilterSuggestionBuilder.js
index a3ea2f88fbe51b00dfcfab29793ec9a8047c696e..ed72af990827c9a59804832854dcc2d303ce087e 100644
--- a/third_party/WebKit/Source/devtools/front_end/network/FilterSuggestionBuilder.js
+++ b/third_party/WebKit/Source/devtools/front_end/network/FilterSuggestionBuilder.js
@@ -80,10 +80,19 @@ Network.FilterSuggestionBuilder = class {
    */
   _values(key) {
     var result = this._valueLists[key];
+    var priorityMap;
+
     if (!result)
       return [];
 
-    result.sort();
+    if (key === 'priority') {

[allada, 2016/12/12 17:29:57]

Instead of storing the symbols lets just make sure we pass in the values (since
they must be unique anyway). Then use an lookup map to get the symbol where
needed.

[Oleksii Kadurin, 2016/12/12 21:13:15]

It could be optimized but I don't feel it could be done too much. The thing is
that the _values function is called in here
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/devtools/front...
and every value here should be transformed label, cause an the line 70
(https://cs.chromium.org/chromium/src/third_party/WebKit/Source/devtools/front...)
there's a comparison of what a user inputted (he/she knows only about
transformed labels like 'lowest'). 
So conclusion #1. All values returned from the _values function should be
transformed.

Then at the line 74
(https://cs.chromium.org/chromium/src/third_party/WebKit/Source/devtools/front...)
they pass array of suggestions that will be shown to user. At this point or
later those should be sorted by priority.
So conclusion #2. Sorting happens here.

But still there's a room for optimization. Sorting should happens after
filtering loop.
  

[allada, 2016/12/12 23:51:08]

Lets first address the two way map from the other comment. Then we can address
this one easier (I think).

[Oleksii Kadurin, 2016/12/13 19:43:37]

Sorry, I still don't get the idea here :(
I will just write my vision of the purpose of this change once again and if
possible, please point out my mistakes.  
So this function returns label that should be displayed in the suggestion box.
Those labels are unique priority labels collected from all requests in the
Network log.
So if the log doesn't contain for instance 'VeryLow' priority, then the function
shouldn't return that value in the array.
Then I request the 'Enum -> numeric priority' map. Then sort unique ENUMS by
priority from the very lowest to the highest.
Then transform all the Enums in the array to corresponding labels.
That array of label will be used for showing labels in the suggestion box.

+      priorityMap = SDK.NetworkRequest.GetSymbolicToNumericPriority();
+      result = result.sort((a, b) => priorityMap.get(b) - priorityMap.get(a));
+      result = result.map(priority => Components.uiLabelForPriority(priority));
+    } else {
+      result.sort();
+    }
+
     return result;
   }