Bug 1751010: Expose command line arguments early enough to detect private browsing mode before window painting r=nika,nalexander,mconley

Differential Revision: https://phabricator.services.mozilla.com/D139988

browser/components/BrowserGlue.jsm

@@ -778,97 +778,6 @@ let JSWINDOWACTORS = {
   },
 };
 
-(function earlyBlankFirstPaint() {
-  let startTime = Cu.now();
-  if (
-    AppConstants.platform == "macosx" ||
-    Services.startup.wasSilentlyStarted ||
-    !Services.prefs.getBoolPref("browser.startup.blankWindow", false)
-  ) {
-    return;
-  }
-
-  // Until bug 1450626 and bug 1488384 are fixed, skip the blank window when
-  // using a non-default theme.
-  if (
-    !Services.startup.showedPreXULSkeletonUI &&
-    Services.prefs.getCharPref(
-      "extensions.activeThemeID",
-      "default-theme@mozilla.org"
-    ) != "default-theme@mozilla.org"
-  ) {
-    return;
-  }
-
-  let store = Services.xulStore;
-  let getValue = attr =>
-    store.getValue(AppConstants.BROWSER_CHROME_URL, "main-window", attr);
-  let width = getValue("width");
-  let height = getValue("height");
-
-  // The clean profile case isn't handled yet. Return early for now.
-  if (!width || !height) {
-    return;
-  }
-
-  let browserWindowFeatures =
-    "chrome,all,dialog=no,extrachrome,menubar,resizable,scrollbars,status," +
-    "location,toolbar,personalbar";
-  let win = Services.ww.openWindow(
-    null,
-    "about:blank",
-    null,
-    browserWindowFeatures,
-    null
-  );
-
-  // Hide the titlebar if the actual browser window will draw in it.
-  let hiddenTitlebar = Services.appinfo.drawInTitlebar;
-  if (hiddenTitlebar) {
-    win.windowUtils.setChromeMargin(0, 2, 2, 2);
-  }
-
-  let docElt = win.document.documentElement;
-  docElt.setAttribute("screenX", getValue("screenX"));
-  docElt.setAttribute("screenY", getValue("screenY"));
-
-  // The sizemode="maximized" attribute needs to be set before first paint.
-  let sizemode = getValue("sizemode");
-  if (sizemode == "maximized") {
-    docElt.setAttribute("sizemode", sizemode);
-
-    // Set the size to use when the user leaves the maximized mode.
-    // The persisted size is the outer size, but the height/width
-    // attributes set the inner size.
-    let appWin = win.docShell.treeOwner
-      .QueryInterface(Ci.nsIInterfaceRequestor)
-      .getInterface(Ci.nsIAppWindow);
-    height -= appWin.outerToInnerHeightDifferenceInCSSPixels;
-    width -= appWin.outerToInnerWidthDifferenceInCSSPixels;
-    docElt.setAttribute("height", height);
-    docElt.setAttribute("width", width);
-  } else {
-    // Setting the size of the window in the features string instead of here
-    // causes the window to grow by the size of the titlebar.
-    win.resizeTo(width, height);
-  }
-
-  // Set this before showing the window so that graphics code can use it to
-  // decide to skip some expensive code paths (eg. starting the GPU process).
-  docElt.setAttribute("windowtype", "navigator:blank");
-
-  // The window becomes visible after OnStopRequest, so make this happen now.
-  win.stop();
-
-  ChromeUtils.addProfilerMarker("earlyBlankFirstPaint", startTime);
-  win.openTime = Cu.now();
-
-  let { TelemetryTimestamps } = ChromeUtils.import(
-    "resource://gre/modules/TelemetryTimestamps.jsm"
-  );
-  TelemetryTimestamps.add("blankWindowShown");
-})();
-
 XPCOMUtils.defineLazyGetter(
   this,
   "WeaveService",
@@ -1187,6 +1096,9 @@ BrowserGlue.prototype = {
         // Allow certain viewable internally types to be opened from downloads.
         DownloadsViewableInternally.register();
 
+        break;
+      case "app-startup":
+        this._earlyBlankFirstPaint(subject);
         break;
     }
   },
@@ -1524,6 +1436,104 @@ BrowserGlue.prototype = {
     );
   },
 
+  _earlyBlankFirstPaint(cmdLine) {
+    let startTime = Cu.now();
+    if (
+      AppConstants.platform == "macosx" ||
+      Services.startup.wasSilentlyStarted ||
+      !Services.prefs.getBoolPref("browser.startup.blankWindow", false)
+    ) {
+      return;
+    }
+
+    // Until bug 1450626 and bug 1488384 are fixed, skip the blank window when
+    // using a non-default theme.
+    if (
+      !Services.startup.showedPreXULSkeletonUI &&
+      Services.prefs.getCharPref(
+        "extensions.activeThemeID",
+        "default-theme@mozilla.org"
+      ) != "default-theme@mozilla.org"
+    ) {
+      return;
+    }
+
+    let store = Services.xulStore;
+    let getValue = attr =>
+      store.getValue(AppConstants.BROWSER_CHROME_URL, "main-window", attr);
+    let width = getValue("width");
+    let height = getValue("height");
+
+    // The clean profile case isn't handled yet. Return early for now.
+    if (!width || !height) {
+      return;
+    }
+
+    let browserWindowFeatures =
+      "chrome,all,dialog=no,extrachrome,menubar,resizable,scrollbars,status," +
+      "location,toolbar,personalbar";
+    // This needs to be set when opening the window to ensure that the AppUserModelID
+    // is set correctly on Windows. Without it, initial launches with `-private-window`
+    // will show up under the regular Firefox taskbar icon first, and then switch
+    // to the Private Browsing icon shortly thereafter.
+    if (cmdLine.findFlag("private-window", false) != -1) {
+      browserWindowFeatures += ",private";
+    }
+    let win = Services.ww.openWindow(
+      null,
+      "about:blank",
+      null,
+      browserWindowFeatures,
+      null
+    );
+
+    // Hide the titlebar if the actual browser window will draw in it.
+    let hiddenTitlebar = Services.appinfo.drawInTitlebar;
+    if (hiddenTitlebar) {
+      win.windowUtils.setChromeMargin(0, 2, 2, 2);
+    }
+
+    let docElt = win.document.documentElement;
+    docElt.setAttribute("screenX", getValue("screenX"));
+    docElt.setAttribute("screenY", getValue("screenY"));
+
+    // The sizemode="maximized" attribute needs to be set before first paint.
+    let sizemode = getValue("sizemode");
+    if (sizemode == "maximized") {
+      docElt.setAttribute("sizemode", sizemode);
+
+      // Set the size to use when the user leaves the maximized mode.
+      // The persisted size is the outer size, but the height/width
+      // attributes set the inner size.
+      let appWin = win.docShell.treeOwner
+        .QueryInterface(Ci.nsIInterfaceRequestor)
+        .getInterface(Ci.nsIAppWindow);
+      height -= appWin.outerToInnerHeightDifferenceInCSSPixels;
+      width -= appWin.outerToInnerWidthDifferenceInCSSPixels;
+      docElt.setAttribute("height", height);
+      docElt.setAttribute("width", width);
+    } else {
+      // Setting the size of the window in the features string instead of here
+      // causes the window to grow by the size of the titlebar.
+      win.resizeTo(width, height);
+    }
+
+    // Set this before showing the window so that graphics code can use it to
+    // decide to skip some expensive code paths (eg. starting the GPU process).
+    docElt.setAttribute("windowtype", "navigator:blank");
+
+    // The window becomes visible after OnStopRequest, so make this happen now.
+    win.stop();
+
+    ChromeUtils.addProfilerMarker("earlyBlankFirstPaint", startTime);
+    win.openTime = Cu.now();
+
+    let { TelemetryTimestamps } = ChromeUtils.import(
+      "resource://gre/modules/TelemetryTimestamps.jsm"
+    );
+    TelemetryTimestamps.add("blankWindowShown");
+  },
+
   _firstWindowTelemetry(aWindow) {
     let scaling = aWindow.devicePixelRatio * 100;
     try {

toolkit/xre/nsAppRunner.cpp

@@ -5466,7 +5466,21 @@ nsresult XREMain::XRE_mainRun() {
     // files can't override JS engine start-up prefs.
     mDirProvider.FinishInitializingUserPrefs();
 
-    nsAppStartupNotifier::NotifyObservers(APPSTARTUP_CATEGORY);
+    nsCOMPtr<nsIFile> workingDir;
+    rv = NS_GetSpecialDirectory(NS_OS_CURRENT_WORKING_DIR,
+                                getter_AddRefs(workingDir));
+    if (NS_FAILED(rv)) {
+      // No working dir? This can happen if it gets deleted before we start.
+      workingDir = nullptr;
+    }
+
+    cmdLine = new nsCommandLine();
+
+    rv = cmdLine->Init(gArgc, gArgv, workingDir,
+                       nsICommandLine::STATE_INITIAL_LAUNCH);
+    NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
+
+    nsAppStartupNotifier::NotifyObservers(APPSTARTUP_CATEGORY, cmdLine);
 
     appStartup = components::AppStartup::Service();
     NS_ENSURE_TRUE(appStartup, NS_ERROR_FAILURE);
@@ -5487,21 +5501,7 @@ nsresult XREMain::XRE_mainRun() {
 
     appStartup->GetShuttingDown(&mShuttingDown);
 
-    nsCOMPtr<nsIFile> workingDir;
-    rv = NS_GetSpecialDirectory(NS_OS_CURRENT_WORKING_DIR,
-                                getter_AddRefs(workingDir));
-    if (NS_FAILED(rv)) {
-      // No working dir? This can happen if it gets deleted before we start.
-      workingDir = nullptr;
-    }
-
     if (!mShuttingDown) {
-      cmdLine = new nsCommandLine();
-
-      rv = cmdLine->Init(gArgc, gArgv, workingDir,
-                         nsICommandLine::STATE_INITIAL_LAUNCH);
-      NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
-
       /* Special-case services that need early access to the command
           line. */
       nsCOMPtr<nsIObserverService> obsService =

toolkit/xre/nsAppStartupNotifier.cpp

@@ -16,7 +16,8 @@
 using namespace mozilla;
 
 /* static */
-nsresult nsAppStartupNotifier::NotifyObservers(const char* aCategory) {
+nsresult nsAppStartupNotifier::NotifyObservers(const char* aCategory,
+                                               nsISupports* aSubject) {
   NS_ENSURE_ARG(aCategory);
   nsresult rv;
 
@@ -53,7 +54,7 @@ nsresult nsAppStartupNotifier::NotifyObservers(const char* aCategory) {
       nsCOMPtr<nsIObserver> startupObserver =
           do_QueryInterface(startupInstance, &rv);
       if (NS_SUCCEEDED(rv)) {
-        rv = startupObserver->Observe(nullptr, aCategory, nullptr);
+        rv = startupObserver->Observe(aSubject, aCategory, nullptr);
 
         // mainly for debugging if you want to know if your observer worked.
         NS_ASSERTION(NS_SUCCEEDED(rv), "Startup Observer failed!\n");

toolkit/xre/nsAppStartupNotifier.h

@@ -11,7 +11,8 @@
 
 class nsAppStartupNotifier final {
  public:
-  static nsresult NotifyObservers(const char* aTopic);
+  static nsresult NotifyObservers(const char* aCategory,
+                                  nsISupports* aSubject = nullptr);
 };
 
 #endif /* nsAppStartupNotifier_h___ */