DevTools: expect length/size hints in descriptions with parenthesis

This CL let's DevTools properly handle array lengths following a change to the
way descriptions are generated in injected-script-source, "Array(10)" instead of
"Array[10]".

Related CL in V8: https://codereview.chromium.org/2521853003

BUG=405845

Review-Url: https://codereview.chromium.org/2524913002
Cr-Commit-Position: refs/heads/master@{#434282}

front_end/sdk/RemoteObject.js

@@ -70,7 +70,7 @@ SDK.RemoteObject = class {
   static arrayLength(object) {
     if (object.subtype !== 'array' && object.subtype !== 'typedarray')
       return 0;
-    var matches = object.description.match(/\[([0-9]+)\]/);
+    var matches = object.description.match(/\[([0-9]+)\]/) || object.description.match(/\(([0-9]+)\)/);
     if (!matches)
       return 0;
     return parseInt(matches[1], 10);