Bug 1689559 - [devtools] Remove devtools.target-switching.enabled preference r=nchevobbe

Differential Revision: https://phabricator.services.mozilla.com/D103452

browser/app/profile/firefox.js

@@ -2119,14 +2119,6 @@ pref("devtools.browsertoolbox.fission", true);
 pref("devtools.browsertoolbox.fission", false);
 #endif
 
-// This pref is also related to fission, but not only. It allows the toolbox
-// to stay open even if the debugged tab switches to another process.
-// It can happen between two documents, one running in the parent process like
-// about:sessionrestore and another one running in the content process like
-// any web page. Or between two distinct domain when running with fission turned
-// on. See bug 1565263.
-pref("devtools.target-switching.enabled", true);
-
 // Toolbox Button preferences
 pref("devtools.command-button-pick.enabled", true);
 pref("devtools.command-button-frames.enabled", true);

devtools/client/devtools-fission-prefs.js

@@ -26,14 +26,6 @@ const PREFERENCES = [
       "Console, so that it can see and debug resources from the content " +
       "processes at the same time as resources from the parent process",
   ],
-  [
-    "devtools.target-switching.enabled",
-    "If you navigate between two distinct process, the toolbox won’t close " +
-      "and will instead switch to the new target. This impacts the regular " +
-      "web toolbox, when switching from eg. about:sessionrestore to any http " +
-      "url (parent process to content process). Or when navigating between " +
-      "two distinct domains if `fission.autostart` is set to true",
-  ],
   [
     "devtools.testing.enableServerWatcherSupport",
     "Enable experimental server-side resources (see watcher actor to get the " +

devtools/client/framework/test/browser_toolbox_remoteness_change.js

@@ -6,21 +6,9 @@ const URL_2 =
   "data:text/html;charset=UTF-8," +
   encodeURIComponent('<div id="remote-page">foo</div>');
 
+// Testing navigation between processes
 add_task(async function() {
-  // Test twice.
-  // Once without target switching, where the toolbox closes and reopens
-  // And a second time, with target switching, where the toolbox stays open
-  await navigateBetweenProcesses(false);
-  await navigateBetweenProcesses(true);
-});
-
-async function navigateBetweenProcesses(enableTargetSwitching) {
-  info(
-    `Testing navigation between processes ${
-      enableTargetSwitching ? "with" : "without"
-    } target switching`
-  );
-  await pushPref("devtools.target-switching.enabled", enableTargetSwitching);
+  info(`Testing navigation between processes`);
 
   info("Open a tab on a URL supporting only running in parent process");
   const tab = await addTab(URL_1);
@@ -35,23 +23,10 @@ async function navigateBetweenProcesses(enableTargetSwitching) {
     "And running in parent process"
   );
 
-  let toolbox = await openToolboxForTab(tab);
-
-  const onToolboxDestroyed = toolbox.once("destroyed");
-  const onToolboxCreated = gDevTools.once("toolbox-created");
-  const onToolboxSwitchedToTarget = toolbox.targetList.once("switched-target");
+  const toolbox = await openToolboxForTab(tab);
 
   info("Navigate to a URL supporting remote process");
-  if (enableTargetSwitching) {
-    await navigateTo(URL_2);
-  } else {
-    // `navigateTo` except the toolbox to be kept open.
-    // So, fallback to BrowserTestUtils helpers in this test when
-    // the target-switching preference is turned off.
-    const onBrowserLoaded = BrowserTestUtils.browserLoaded(tab.linkedBrowser);
-    BrowserTestUtils.loadURI(tab.linkedBrowser, URL_2);
-    await onBrowserLoaded;
-  }
+  await navigateTo(URL_2);
 
   is(
     tab.linkedBrowser.getAttribute("remote"),
@@ -59,20 +34,6 @@ async function navigateBetweenProcesses(enableTargetSwitching) {
     "Navigated to a data: URI and switching to remote"
   );
 
-  if (enableTargetSwitching) {
-    info("Waiting for the toolbox to be switched to the new target");
-    await onToolboxSwitchedToTarget;
-  } else {
-    info("Waiting for the toolbox to be destroyed");
-    await onToolboxDestroyed;
-
-    info("Waiting for a new toolbox to be created");
-    toolbox = await onToolboxCreated;
-
-    info("Waiting for the new toolbox to be ready");
-    await toolbox.once("ready");
-  }
-
   info("Veryify we are inspecting the new document");
   const console = await toolbox.selectTool("webconsole");
   const { ui } = console.hud;
@@ -88,4 +49,4 @@ async function navigateBetweenProcesses(enableTargetSwitching) {
   const { client } = toolbox.target;
   await toolbox.destroy();
   ok(client._closed, "The client is closed after closing the toolbox");
-}
+});

devtools/client/fronts/descriptors/tab.js

@@ -3,7 +3,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
-const Services = require("Services");
 const { tabDescriptorSpec } = require("devtools/shared/specs/descriptors/tab");
 
 loader.lazyRequireGetter(
@@ -18,12 +17,6 @@ loader.lazyRequireGetter(
   "devtools/client/fronts/targets/browsing-context",
   true
 );
-loader.lazyRequireGetter(
-  this,
-  "TargetFactory",
-  "devtools/client/framework/target",
-  true
-);
 const {
   FrontClassWithSpec,
   registerFront,
@@ -232,30 +225,9 @@ class TabDescriptorFront extends FrontClassWithSpec(tabDescriptorSpec) {
       return;
     }
 
-    const toolbox = gDevTools.getToolbox(this._targetFront);
-
-    const targetSwitchingEnabled = Services.prefs.getBoolPref(
-      "devtools.target-switching.enabled",
-      false
-    );
-
-    // When target switching is enabled, everything is handled by the TargetList
     // In a near future, this client side code should be replaced by actor code,
     // notifying about new tab targets.
-    if (targetSwitchingEnabled) {
-      this.emit("remoteness-change", this._targetFront);
-      return;
-    }
-
-    // Otherwise, if we don't support target switching, ensure the toolbox is destroyed.
-    // We need to wait for the toolbox destruction because the TargetFactory memoized the targets,
-    // and only cleans up the cache after the target is destroyed via toolbox destruction.
-    await toolbox.destroy();
-
-    // Fetch the new target for this tab
-    const newTarget = await TargetFactory.forTab(this.localTab, null);
-
-    gDevTools.showToolbox(newTarget);
+    this.emit("remoteness-change", this._targetFront);
   }
 }
 

devtools/client/shared/test/shared-head.js

@@ -493,17 +493,6 @@ async function navigateTo(uri, { isErrorPage = false } = {}) {
   const switchedToAnotherProcess =
     currentPID !== browser.browsingContext.currentWindowGlobal.osPid;
 
-  // If we switched to another process and the target switching pref is false,
-  // the toolbox will close and reopen.
-  // For now, this helper doesn't support this case
-  if (switchedToAnotherProcess && !isTargetSwitchingEnabled()) {
-    ok(
-      false,
-      `navigateTo(${uri}) navigated to another process, but the target switching is disabled`
-    );
-    return;
-  }
-
   if (onPanelReloaded) {
     info(`Waiting for ${toolbox.currentToolId} to be reloaded…`);
     await onPanelReloaded();
@@ -562,10 +551,6 @@ function isFissionEnabled() {
   return SpecialPowers.useRemoteSubframes;
 }
 
-function isTargetSwitchingEnabled() {
-  return Services.prefs.getBoolPref("devtools.target-switching.enabled", false);
-}
-
 /**
  * Open the inspector in a tab with given URL.
  * @param {string} url  The URL to open.

devtools/client/webconsole/test/browser/browser_webconsole_sandbox_update_after_navigation.js

@@ -44,7 +44,7 @@ add_task(async function() {
   // continuing the test or it might destroy messages we wait later on (Bug
   // 1270234).
   const promises = [hud.ui.once("messages-cleared")];
-  if (isFissionEnabled() && isTargetSwitchingEnabled()) {
+  if (isFissionEnabled()) {
     promises.push(hud.targetList.once("switched-target"));
   }