DevTools: add command menu entries for adding new snippet, workspace folder

BUG=718185

Review-Url: https://codereview.chromium.org/2859533004
Cr-Commit-Position: refs/heads/master@{#469496}

third_party/WebKit/Source/devtools/front_end/sources/SourcesNavigator.js

@@ -277,3 +277,27 @@ Sources.SnippetsNavigatorView = class extends Sources.NavigatorView {
     this._handleRemoveSnippet(uiSourceCode);
   }
 };
+
+/**
+ * @implements {UI.ActionDelegate}
+ */
+Sources.SourcesNavigatorView.CreatingActionDelegate = class {
+  /**
+   * @override
+   * @param {!UI.Context} context
+   * @param {string} actionId
+   * @return {boolean}
+   */
+  handleAction(context, actionId) {
+    switch (actionId) {
+      case 'sources.create-snippet':
+        var uiSourceCode = Snippets.scriptSnippetModel.createScriptSnippet('');
+        Common.Revealer.reveal(uiSourceCode);
+        return true;
+      case 'sources.add-folder-to-workspace':
+        Workspace.isolatedFileSystemManager.addFileSystem();
+        return true;
+    }
+    return false;
+  }
+};

third_party/WebKit/Source/devtools/front_end/sources/module.json

@@ -495,6 +495,20 @@
             "className": "Sources.SourcesView.CloseAllActionDelegate",
             "title": "Close All"
         },
+        {
+            "type": "@UI.ActionDelegate",
+            "category": "Sources",
+            "actionId": "sources.create-snippet",
+            "className": "Sources.SourcesNavigatorView.CreatingActionDelegate",
+            "title": "Create new snippet"
+        },
+        {
+            "type": "@UI.ActionDelegate",
+            "category": "Sources",
+            "actionId": "sources.add-folder-to-workspace",
+            "className": "Sources.SourcesNavigatorView.CreatingActionDelegate",
+            "title": "Add folder to workspace"
+        },
         {
             "type": "@UI.ViewLocationResolver",
             "name": "navigator-view",