Bug 1753939 - [remote] Do not create message handlers for webextension contexts r=webdriver-reviewers,rpl,whimboo

Differential Revision: https://phabricator.services.mozilla.com/D138523

remote/shared/messagehandler/test/browser/browser_session_data_browser_element.js

@@ -8,17 +8,39 @@ const TEST_PAGE = "https://example.com/document-builder.sjs?html=tab";
 /**
  * Check that message handlers are not created for parent process browser
  * elements, even if they have the type="content" attribute (eg used for the
- * DevTools toolbox).
+ * DevTools toolbox), as well as for webextension contexts.
  */
 add_task(async function test_session_data_broadcast() {
+  // Prepare:
+  // - one content tab
+  // - one browser type content
+  // - one browser type chrome
+  // - one sidebar webextension
+  // We only expect session data to be applied to the content tab
   const tab1 = BrowserTestUtils.addTab(gBrowser, TEST_PAGE);
   const contentBrowser1 = tab1.linkedBrowser;
   await BrowserTestUtils.browserLoaded(contentBrowser1);
   const parentBrowser1 = createParentBrowserElement(tab1, "content");
   const parentBrowser2 = createParentBrowserElement(tab1, "chrome");
+  const {
+    extension: extension1,
+    sidebarBrowser: extSidebarBrowser1,
+  } = await installSidebarExtension();
 
   const root = createRootMessageHandler("session-id-event");
 
+  // When the windowglobal command.jsm module applies the session data
+  // browser_session_data_browser_element, it will emit an internal event.
+  // Collect the events to detect which MessageHandlers have been started.
+  info("Watch internal events emitted when session data is applied");
+  const sessionDataEvents = [];
+  const onRootEvent = function(evtName, wrappedEvt) {
+    if (wrappedEvt.name === "received-session-data") {
+      sessionDataEvents.push(wrappedEvt.data.contextId);
+    }
+  };
+  root.on("message-handler-event", onRootEvent);
+
   info("Add a new session data item, expect one return value");
   await root.addSessionData({
     moduleName: "command",
@@ -29,12 +51,17 @@ add_task(async function test_session_data_broadcast() {
     values: [true],
   });
 
+  function hasSessionData(browsingContext) {
+    return sessionDataEvents.includes(browsingContext.id);
+  }
+
   info(
     "Check that only the content tab window global received the session data"
   );
-  is(await hasSessionDataFlag(contentBrowser1), true);
-  is(await hasSessionDataFlag(parentBrowser1), undefined);
-  is(await hasSessionDataFlag(parentBrowser2), undefined);
+  is(hasSessionData(contentBrowser1.browsingContext), true);
+  is(hasSessionData(parentBrowser1.browsingContext), false);
+  is(hasSessionData(parentBrowser2.browsingContext), false);
+  is(hasSessionData(extSidebarBrowser1.browsingContext), false);
 
   const tab2 = BrowserTestUtils.addTab(gBrowser, TEST_PAGE);
   const contentBrowser2 = tab2.linkedBrowser;
@@ -42,23 +69,30 @@ add_task(async function test_session_data_broadcast() {
   const parentBrowser3 = createParentBrowserElement(contentBrowser2, "content");
   const parentBrowser4 = createParentBrowserElement(contentBrowser2, "chrome");
 
+  const {
+    extension: extension2,
+    sidebarBrowser: extSidebarBrowser2,
+  } = await installSidebarExtension();
+
   info("Wait until the session data was applied to the new tab");
-  await SpecialPowers.spawn(contentBrowser2, [], async () => {
-    await ContentTaskUtils.waitForCondition(() => content.hasSessionDataFlag);
-  });
+  await TestUtils.waitForCondition(() =>
+    sessionDataEvents.includes(contentBrowser2.browsingContext.id)
+  );
 
   info("Check that parent browser elements did not apply the session data");
-  is(await hasSessionDataFlag(parentBrowser3), undefined);
-  is(await hasSessionDataFlag(parentBrowser4), undefined);
+  is(hasSessionData(parentBrowser3.browsingContext), false);
+  is(hasSessionData(parentBrowser4.browsingContext), false);
+
+  info(
+    "Check that extension did not apply the session data, " +
+      extSidebarBrowser2.browsingContext.id
+  );
+  is(hasSessionData(extSidebarBrowser2.browsingContext), false);
 
   root.destroy();
 
   gBrowser.removeTab(tab1);
   gBrowser.removeTab(tab2);
+  await extension1.unload();
+  await extension2.unload();
 });
-
-function hasSessionDataFlag(browser) {
-  return SpecialPowers.spawn(browser, [], () => {
-    return content.hasSessionDataFlag;
-  });
-}

remote/shared/messagehandler/test/browser/head.js

@@ -113,3 +113,52 @@ function createTestMarkupWithFrames() {
     TEST_URI_MARKUP
   )}`;
 }
+
+/**
+ * Install a sidebar extension.
+ *
+ * @return {Object}
+ *     Return value with two properties:
+ *     - extension: test wrapper as returned by SpecialPowers.loadExtension.
+ *       Make sure to explicitly call extension.unload() before the end of the test.
+ *     - sidebarBrowser: the browser element containing the extension sidebar.
+ */
+async function installSidebarExtension() {
+  info("Load the test extension");
+  let extension = ExtensionTestUtils.loadExtension({
+    manifest: {
+      sidebar_action: {
+        default_panel: "sidebar.html",
+      },
+    },
+    useAddonManager: "temporary",
+
+    files: {
+      "sidebar.html": `
+        <!DOCTYPE html>
+        <html>
+          Test extension
+          <script src="sidebar.js"></script>
+        </html>
+      `,
+      "sidebar.js": function() {
+        browser.test.sendMessage("sidebar-loaded", {
+          bcId: SpecialPowers.wrap(window).browsingContext.id,
+        });
+      },
+    },
+  });
+
+  info("Wait for the extension to start");
+  await extension.startup();
+
+  info("Wait for the extension browsing context");
+  const { bcId } = await extension.awaitMessage("sidebar-loaded");
+  const sidebarBrowser = BrowsingContext.get(bcId).top.embedderElement;
+  ok(sidebarBrowser, "Got a browser element for the extension sidebar");
+
+  return {
+    extension,
+    sidebarBrowser,
+  };
+}

remote/shared/messagehandler/test/browser/resources/modules/windowglobal/command.jsm

@@ -41,9 +41,9 @@ class Command extends Module {
     }
 
     if (params.category === "browser_session_data_browser_element") {
-      BrowsingContext.get(
-        this.messageHandler.contextId
-      ).window.hasSessionDataFlag = true;
+      this.emitEvent("received-session-data", {
+        contextId: this.messageHandler.contextId,
+      });
     }
 
     return {};

remote/shared/messagehandler/transports/js-window-actors/MessageHandlerFrameActor.jsm

@@ -30,6 +30,7 @@ const FRAME_ACTOR_CONFIG = {
     },
   },
   allFrames: true,
+  messageManagerGroups: ["browsers"],
 };
 
 /**