Bug 1066383, rework custom html menu item handling to support contextmenu attribute in separate process, r=janv,mconley,peterv

dom/html/htmlMenuBuilder.js

@@ -0,0 +1,132 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// This component is used to build the menus for the HTML contextmenu attribute.
+
+Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
+
+const Cc = Components.classes;
+const Ci = Components.interfaces;
+
+// A global value that is used to identify each menu item. It is
+// incremented with each one that is found.
+var gGeneratedId = 1;
+
+function HTMLMenuBuilder() {
+  this.currentNode = null;
+  this.root = null;
+  this.items = {};
+  this.nestedStack = [];
+};
+
+// Building is done in two steps:
+// The first generates a hierarchical JS object that contains the menu structure.
+// This object is returned by toJSONString.
+//
+// The second step can take this structure and generate a XUL menu hierarchy or
+// other UI from this object. The default UI is done in PageMenu.jsm.
+//
+// When a multi-process browser is used, the first step is performed by the child
+// process and the second step is performed by the parent process.
+
+HTMLMenuBuilder.prototype =
+{
+  classID:        Components.ID("{51c65f5d-0de5-4edc-9058-60e50cef77f8}"),
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIMenuBuilder]),
+
+  currentNode: null,
+  root: null,
+  items: {},
+  nestedStack: [],
+
+  toJSONString: function() {
+    return JSON.stringify(this.root);
+  },
+
+  openContainer: function(aLabel) {
+    if (!this.currentNode) {
+      this.root = {
+        type: "menu",
+        children: []
+      };
+      this.currentNode = this.root;
+    }
+    else {
+      let parent = this.currentNode;
+      this.currentNode = {
+        type: "menu",
+        label: aLabel,
+        children: []
+      };
+      parent.children.push(this.currentNode);
+      this.nestedStack.push(parent);
+    }
+  },
+
+  addItemFor: function(aElement, aCanLoadIcon) {
+    if (!("children" in this.currentNode)) {
+      return;
+    }
+
+    let item = {
+      type: "menuitem",
+      label: aElement.label
+    };
+
+    let elementType = aElement.type;
+    if (elementType == "checkbox" || elementType == "radio") {
+      item.checkbox = true;
+
+      if (aElement.checked) {
+        item.checked = true;
+      }
+    }
+
+    let icon = aElement.icon;
+    if (icon.length > 0 && aCanLoadIcon) {
+      item.icon = icon;
+    }
+
+    if (aElement.disabled) {
+      item.disabled = true;
+    }
+
+    item.id = gGeneratedId++;
+    this.currentNode.children.push(item);
+
+    this.items[item.id] = aElement;
+  },
+
+  addSeparator: function() {
+    if (!("children" in this.currentNode)) {
+      return;
+    }
+
+    this.currentNode.children.push({ type: "separator"});
+  },
+
+  undoAddSeparator: function() {
+    if (!("children" in this.currentNode)) {
+      return;
+    }
+
+    let children = this.currentNode.children;
+    if (children.length && children[children.length - 1].type == "separator") {
+      children.pop();
+    }
+  },
+
+  closeContainer: function() {
+    this.currentNode = this.nestedStack.length ? this.nestedStack.pop() : this.root;
+  },
+
+  click: function(id) {
+    let item = this.items[id];
+    if (item) {
+      item.click();
+    }
+  }
+};
+
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory([HTMLMenuBuilder]);