Bug 1224105 - [webext] Use <browser> element for background page (r=kmag)

toolkit/components/extensions/ext-backgroundPage.js

@@ -13,14 +13,15 @@ function BackgroundPage(options, extension) {
   this.scripts = options.scripts || [];
   this.page = options.page || null;
   this.contentWindow = null;
+  this.chromeWebNav = null;
   this.webNav = null;
   this.context = null;
 }
 
 BackgroundPage.prototype = {
   build() {
-    let webNav = Services.appShell.createWindowlessBrowser(false);
-    this.webNav = webNav;
+    let chromeWebNav = Services.appShell.createWindowlessBrowser(true);
+    this.chromeWebNav = chromeWebNav;
 
     let url;
     if (this.page) {
@@ -38,20 +39,35 @@ BackgroundPage.prototype = {
     let uri = Services.io.newURI(url, null, null);
     let principal = this.extension.createPrincipal(uri);
 
-    let interfaceRequestor = webNav.QueryInterface(Ci.nsIInterfaceRequestor);
-    let docShell = interfaceRequestor.getInterface(Ci.nsIDocShell);
+    let system = Services.scriptSecurityManager.getSystemPrincipal();
+    let interfaceRequestor = chromeWebNav.QueryInterface(Ci.nsIInterfaceRequestor);
+    let chromeShell = interfaceRequestor.getInterface(Ci.nsIDocShell);
+    chromeShell.createAboutBlankContentViewer(system);
+
+    let chromeDoc = chromeWebNav.document;
+    const XUL_NS = "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
+    let browser = chromeDoc.createElementNS(XUL_NS, "browser");
+    browser.setAttribute("type", "content");
+    browser.setAttribute("disableglobalhistory", "true");
+    chromeDoc.body.appendChild(browser);
+
+    let frameLoader = browser.QueryInterface(Ci.nsIFrameLoaderOwner).frameLoader;
+    let docShell = frameLoader.docShell;
 
     this.context = new ExtensionPage(this.extension, {type: "background", docShell, uri});
     GlobalManager.injectInDocShell(docShell, this.extension, this.context);
 
     docShell.createAboutBlankContentViewer(principal);
 
+    let webNav = docShell.QueryInterface(Ci.nsIWebNavigation);
+    this.webNav = webNav;
+
+    webNav.loadURI(url, 0, null, null, null);
+
     let window = webNav.document.defaultView;
     this.contentWindow = window;
     this.context.contentWindow = window;
 
-    webNav.loadURI(url, 0, null, null, null);
-
     // TODO: Right now we run onStartup after the background page
     // finishes. See if this is what Chrome does.
     let loadListener = event => {
@@ -59,6 +75,7 @@ BackgroundPage.prototype = {
         return;
       }
       event.currentTarget.removeEventListener("load", loadListener, true);
+
       if (this.scripts) {
         let doc = window.document;
         for (let script of this.scripts) {
@@ -80,7 +97,7 @@ BackgroundPage.prototype = {
         this.extension.onStartup();
       }
     };
-    window.windowRoot.addEventListener("load", loadListener, true);
+    browser.addEventListener("load", loadListener, true);
   },
 
   shutdown() {
@@ -88,6 +105,9 @@ BackgroundPage.prototype = {
     // setTimeouts or other callbacks.
     this.webNav.loadURI("about:blank", 0, null, null, null);
     this.webNav = null;
+
+    this.chromeWebNav.loadURI("about:blank", 0, null, null, null);
+    this.chromeWebNav = null;
   },
 };