[DevTools] Shows Manifest file in Sources tab

 - Adds Manifest resource type in Resource.h and RawResource::fetchManifest().
 - Uses RawResource::fetchManifest() in DocumentThreadableLoader.
 - Adds Manifest resource type in InspectorPageAgent.h.
 - Adds Manifest resource type in protocol.json.
 - Changes InspectorPageAgent::cachedResourceType() and resourceTypeJson() to support Manifest resource type.
 - Changes WebInspector.NetworkProject._addResource() to show the manifest file in Sources tab.
 - Changes WebConsoleMessage.h to support url.
 - Changes manifest_manager.cc to pass the manifest url.

demo: https://drive.google.com/file/d/0B6skYAFVnosEN1UzWktHUTRUdUE/view?usp=sharing

BUG=540493

Review URL: https://codereview.chromium.org/1564913003

Cr-Commit-Position: refs/heads/master@{#368308}

front_end/bindings/NetworkProject.js

@@ -343,7 +343,8 @@ WebInspector.NetworkProject.prototype = {
         // Only load selected resource types from resources.
         if (resourceType !== WebInspector.resourceTypes.Image &&
             resourceType !== WebInspector.resourceTypes.Font &&
-            resourceType !== WebInspector.resourceTypes.Document) {
+            resourceType !== WebInspector.resourceTypes.Document &&
+            resourceType !== WebInspector.resourceTypes.Manifest) {
             return;
         }
 

front_end/common/ResourceType.js

@@ -167,6 +167,7 @@ WebInspector.resourceCategories = {
     Font: new WebInspector.ResourceCategory("Fonts", "Font"),
     Document: new WebInspector.ResourceCategory("Documents", "Doc"),
     WebSocket: new WebInspector.ResourceCategory("WebSockets", "WS"),
+    Manifest: new WebInspector.ResourceCategory("Manifest", "Manifest"),
     Other: new WebInspector.ResourceCategory("Other", "Other")
 }
 
@@ -189,6 +190,7 @@ WebInspector.resourceTypes = {
     Other: new WebInspector.ResourceType("other", "Other", WebInspector.resourceCategories.Other, false),
     SourceMapScript: new WebInspector.ResourceType("sm-script", "Script", WebInspector.resourceCategories.Script, false),
     SourceMapStyleSheet: new WebInspector.ResourceType("sm-stylesheet", "Stylesheet", WebInspector.resourceCategories.Stylesheet, false),
+    Manifest: new WebInspector.ResourceType("manifest", "Manifest", WebInspector.resourceCategories.Manifest, false),
 }
 
 /**

protocol.json

@@ -90,7 +90,7 @@
             {
                 "id": "ResourceType",
                 "type": "string",
-                "enum": ["Document", "Stylesheet", "Image", "Media", "Font", "Script", "TextTrack", "XHR", "Fetch", "EventSource", "WebSocket", "Other"],
+                "enum": ["Document", "Stylesheet", "Image", "Media", "Font", "Script", "TextTrack", "XHR", "Fetch", "EventSource", "WebSocket", "Manifest", "Other"],
                 "description": "Resource type as it was perceived by the rendering engine."
             },
             {