rewrite: Flag exposure

patches/add-incognito-launch-feature.patch

@@ -0,0 +1,83 @@
+diff --git a/chrome/browser/prefs/incognito_mode_prefs.cc b/chrome/browser/prefs/incognito_mode_prefs.cc
+index 252de88cbf948..37116fc4fba56 100644
+--- a/chrome/browser/prefs/incognito_mode_prefs.cc
++++ b/chrome/browser/prefs/incognito_mode_prefs.cc
+@@ -17,6 +17,7 @@
+ #include "components/policy/core/common/policy_pref_names.h"
+ #include "components/pref_registry/pref_registry_syncable.h"
+ #include "components/prefs/pref_service.h"
++#include "chrome/common/chrome_features.cc"
+
+ #if BUILDFLAG(IS_WIN)
+ #include "chrome/browser/win/parental_controls.h"
+@@ -154,7 +155,8 @@ bool IncognitoModePrefs::ShouldLaunchIncognitoInternal(
+   // to launch in incognito mode or if it was forced via prefs. This way,
+   // the parental controls check (which can be quite slow) can be avoided
+   // most of the time.
+-  bool forced_by_switch = command_line.HasSwitch(switches::kIncognito);
++  bool forced_by_switch = command_line.HasSwitch(switches::kIncognito) ||
++		base::FeatureList::IsEnabled(features::kIncognitoLaunch);
+   if (for_subsequent_browsers) {
+     forced_by_switch =
+         forced_by_switch &&
+diff --git a/chrome/browser/ui/startup/startup_browser_creator.cc b/chrome/browser/ui/startup/startup_browser_creator.cc
+index 8740af9bc6cd6..0019f14966239 100644
+--- a/chrome/browser/ui/startup/startup_browser_creator.cc
++++ b/chrome/browser/ui/startup/startup_browser_creator.cc
+@@ -344,6 +344,7 @@ StartupProfileModeReason ShouldShowProfilePickerAtProcessLaunch(
+                                      g_browser_process->local_state(),
+                                      /*show_warning=*/false) ||
+       command_line.HasSwitch(switches::kIncognito) ||
++      base::FeatureList::IsEnabled(features::kIncognitoLaunch) ||
+       has_command_line_specified_profile_directory) {
+     // TODO(crbug.com/40257919): The profile directory and guest mode
+     // were already tested in the calling function `GetStartupProfilePath()`.
+@@ -421,7 +422,9 @@ Profile* GetPrivateProfileIfRequested(const base::CommandLine& command_line,
+                                                 profile->GetPrefs())) {
+     return profile->GetPrimaryOTRProfile(/*create_if_needed=*/true);
+   } else {
+-    bool expect_incognito = command_line.HasSwitch(switches::kIncognito);
++    bool expect_incognito = command_line.HasSwitch(switches::kIncognito) ||
++	                    base::FeatureList::IsEnabled(
++						features::kIncognitoLaunch);
+     LOG_IF(WARNING, expect_incognito)
+         << "Incognito mode disabled by policy, launching a normal "
+         << "browser session.";
+@@ -999,7 +1002,9 @@ bool StartupBrowserCreator::ProcessCmdLineImpl(
+       CanOpenProfileOnStartup(profile_info) && !should_launch_incognito;
+
+   RecordIncognitoForcedStart(should_launch_incognito,
+-                             command_line.HasSwitch(switches::kIncognito));
++                             command_line.HasSwitch(switches::kIncognito) ||
++			     base::FeatureList::IsEnabled(
++						features::kIncognitoLaunch));
+
+   // `profile` is never off-the-record. If Incognito or Guest enforcement switch
+   // or policy are provided, use the appropriate private browsing profile
+diff --git a/chrome/common/chrome_features.cc b/chrome/common/chrome_features.cc
+index f3224987d31d6..67a1a5ecf15e1 100644
+--- a/chrome/common/chrome_features.cc
++++ b/chrome/common/chrome_features.cc
+@@ -17,6 +17,9 @@ namespace features {
+
+ // All features in alphabetical order.
+
++BASE_FEATURE(kIncognitoLaunch, "IncognitoLaunch",
++	base::FEATURE_DISABLED_BY_DEFAULT);
++
+ #if BUILDFLAG(IS_CHROMEOS_ASH)
+ // If enabled device status collector will add the type of session (Affiliated
+ // User, Kiosks, Managed Guest Sessions) to the device status report.
+diff --git a/chrome/common/chrome_features.h b/chrome/common/chrome_features.h
+index fc691fad58cbd..6c506b3fc555a 100644
+--- a/chrome/common/chrome_features.h
++++ b/chrome/common/chrome_features.h
+@@ -25,6 +25,8 @@
+
+ namespace features {
+
++BASE_DECLARE_FEATURE(kIncognitoLaunch);
++
+ // All features in alphabetical order. The features should be documented
+ // alongside the definition of their values in the .cc file.
+

patches/expose-flags.patch

@@ -1,89 +1,41 @@
 diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
-index f705f4aa8b568..145eb17541758 100644
+index 96370d4ac35a9..bc80527377261 100644
 --- a/chrome/browser/about_flags.cc
 +++ b/chrome/browser/about_flags.cc
-@@ -4133,6 +4133,26 @@ const FeatureEntry kFeatureEntries[] = {
+@@ -4190,6 +4190,36 @@ const FeatureEntry kFeatureEntries[] = {
  // //tools/flags/generate_unexpire_flags.py.
  #include "build/chromeos_buildflags.h"
  #include "chrome/browser/unexpire_flags_gen.inc"
 +    {"incognito-launch",
 +     "Incognito Launch",
-+     "Incognito mode on launch. This flag is exposed by hardened-chromium.",
-+     kOsAll, SINGLE_VALUE_TYPE("incognito")},
++     "Launch external links and open new sessions in Incognito. Disabled by "
++     "default. This flag is provided by hardened-chromium.",
++     kOsAll, FEATURE_VALUE_TYPE(features::kIncognitoLaunch)},
++    {"extensions-support",
++     "Extensions Support",
++     "Toggle extensions support. This flag is exposed by hardened-chromium.",
++     kOsAll, SINGLE_DISABLE_VALUE_TYPE("disable-extensions")},
 +    {"disable-cross-origin-referrers",
-+     flag_descriptions::kDisableCrossOriginReferrersName,
-+     flag_descriptions::kDisableCrossOriginReferrersDescription, kOsAll,
++     "Clear cross-origin referrers",
++     "Clears referrers when navigating across origins. Defaults to disabled. "
++     "This feature is provided by hardened-chromium.", kOsAll,
 +     FEATURE_VALUE_TYPE(net::features::kDisableCrossOriginReferrers)},
 +    {"cross-origin-trim-referrer",
-+     flag_descriptions::kCapReferrerToOriginOnCrossOriginName,
-+     flag_descriptions::kCapReferrerToOriginOnCrossOriginDescription, kOsAll,
++     "Cross-origin referrer trimming",
++     "Trims the referrer to just the origin on cross origin navigation. "
++     "Defaults to enabled. This feature is exposed by hardened-chromium.",
++     kOsAll,
 +     FEATURE_VALUE_TYPE(net::features::kCapReferrerToOriginOnCrossOrigin)},
 +    {"hide-profile-icon",
-+     flag_descriptions::kHideProfileIconName,
-+     flag_descriptions::kHideProfileIconDescription, kOsAll,
++     "Hide profile icon in toolbar",
++     "Hides the profile icon in the toolbar in regular profiles. Defaults "
++     "to enabled. This feature is provided by hardened-chromium." , kOsAll,
 +     FEATURE_VALUE_TYPE(features::kHideProfileIcon)},
 +    {"show-punycode-domains",
-+     flag_descriptions::kShowPunycodeDomainsName,
-+     flag_descriptions::kShowPunycodeDomainsDescription, kOsAll,
-+     FEATURE_VALUE_TYPE(url::kShowPunycodeDomains)},
++     "Show punycode for IDN domains",
++     "Shows punycode for IDN domains to mitigate IDN homograph attacks. "
++     "Defaults to disabled. This feature is provided by hardened-chromium.",
++     kOsAll, FEATURE_VALUE_TYPE(url::kShowPunycodeDomains)},
      {variations::switches::kEnableBenchmarking,
       flag_descriptions::kEnableBenchmarkingName,
       flag_descriptions::kEnableBenchmarkingDescription, kOsAll,
-diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
-index 695e4f8ba74d0..b82fdbd37d370 100644
---- a/chrome/browser/flag_descriptions.cc
-+++ b/chrome/browser/flag_descriptions.cc
-@@ -14,6 +14,28 @@
-
- namespace flag_descriptions {
-
-+const char kDisableCrossOriginReferrersName[] =
-+    "Clear cross-origin referrers";
-+const char kDisableCrossOriginReferrersDescription[] =
-+    "Clears referrers when navigating across origins. Defaults to disabled. "
-+    "This feature is provided by hardened-chromium.";
-+
-+const char kCapReferrerToOriginOnCrossOriginName[] =
-+    "Cross-origin referrer trimming";
-+const char kCapReferrerToOriginOnCrossOriginDescription[] =
-+    "Trims the referrer to just the origin on cross origin navigation. "
-+    "Defaults to enabled. This feature is exposed by hardened-chromium.";
-+
-+const char kHideProfileIconName[] = "Hide profile icon in toolbar";
-+const char kHideProfileIconDescription[] =
-+    "Hides the profile icon in the toolbar in regular profiles. Defaults "
-+    "to enabled. This feature is provided by hardened-chromium.";
-+
-+const char kShowPunycodeDomainsName[] = "Show punycode for IDN domains";
-+const char kShowPunycodeDomainsDescription[] =
-+    "Shows punycode for IDN domains to mitigate IDN homograph attacks. "
-+    "Defaults to disabled. This feature is provided by hardened-chromium.";
-+
- const char kAccelerated2dCanvasName[] = "Accelerated 2D canvas";
- const char kAccelerated2dCanvasDescription[] =
-     "Enables the use of the GPU to perform 2d canvas rendering instead of "
-diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
-index 83c2d22343339..ef1975e1ea895 100644
---- a/chrome/browser/flag_descriptions.h
-+++ b/chrome/browser/flag_descriptions.h
-@@ -43,6 +43,20 @@
-
- namespace flag_descriptions {
-
-+// hardened chromium ----------------------------------------------------------
-+
-+extern const char kDisableCrossOriginReferrersName[];
-+extern const char kDisableCrossOriginReferrersDescription[];
-+
-+extern const char kCapReferrerToOriginOnCrossOriginName[];
-+extern const char kCapReferrerToOriginOnCrossOriginDescription[];
-+
-+extern const char kHideProfileIconName[];
-+extern const char kHideProfileIconDescription[];
-+
-+extern const char kShowPunycodeDomainsName[];
-+extern const char kShowPunycodeDomainsDescription[];
-+
- // Cross-platform -------------------------------------------------------------
-
- extern const char kAccelerated2dCanvasName[];