Public Sessions - prompt the user for pageCapture requests

chrome/common/pref_names.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/pref_names.h"
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "chrome/common/features.h"
 #include "chrome/common/pref_font_webkit_names.h"
@@ skipping 1314 matching lines @@
 #if !defined(OS_ANDROID)
 // Whether or not this profile has been shown the Welcome page.
 const char kHasSeenWelcomePage[] = "browser.has_seen_welcome_page";
 #endif
 
 #if defined(OS_WIN)
 // Whether or not this profile has been shown the Win10 promo page.
 const char kHasSeenWin10PromoPage[] = "browser.has_seen_win10_promo_page";
 #endif
 
 // *************** LOCAL STATE ***************

[gab, 2017/01/09 20:06:43]

Prefs below this line are stored in Local State. Yours is a profile prefs and
therefore belongs in an OS_CHROMEOS block above this line (same in header).

[Ivan Šandrk, 2017/01/09 20:25:54]

Can you perhaps explain me the difference? I'm quite unsure of the whole
placement of my pref.

Basically I need the pref to be non-persistent across user sessions, that's why
I added that line in pref_service_syncable_util.cc. I hope that's an ok usage.

[gab, 2017/01/09 20:47:01]

Local State is for browser-wide prefs.
Preferences are per-profile prefs.

Either way, prefs are specifically meant to be persisted to disk. If you don't
want persistence, don't use prefs (store it in memory in a member of a class of
yours).

[Ivan Šandrk, 2017/01/11 17:41:50]

Thanks for the explanation gab.

I learned today that everything is wiped clean in Public Sessions, so no prefs
will be persisted which is perfect.

 // These are attached to the machine/installation
 
 // Directory of the last profile used.
 const char kProfileLastUsed[] = "profile.last_used";
 
 // List of directories of the profiles last active.
 const char kProfilesLastActive[] = "profile.last_active_profiles";
 
 // Total number of profiles created for this Chrome build. Used to tag profile
 // directories.
@@ skipping 549 matching lines @@
 const char kReportArcStatusEnabled[] = "arc.status_reporting_enabled";
 
 // Dictionary indicating current network bandwidth throttling settings.
 // Contains a boolean (is throttling enabled) and two integers (upload rate
 // and download rate in kbits/s to throttle to)
 const char kNetworkThrottlingEnabled[] = "net.throttling_enabled";
 
 // Boolean prefs for the local status of the touchscreen.
 const char kTouchscreenEnabledLocal[] = "events.touch_screen.enabled_local";
 
+// Dictionary saving user choices regarding granted permissions to
+// extensions/apps for usage of APIs. In Public Sessions API usage is restricted
+// to protect the user from a malicious device owner/admin. This dictionary will
+// not be persisted across sessions.
+const char kPublicSessionPermissionsUserChoiceCache[] =
+    "public_session.permissions.user_choice_cache";

[gab, 2017/01/09 20:06:43]

I don't see existing public_session.* prefs. With "permissions." This will
create two levels of JSON nesting for a single item, can an existing root be
re-used?

[Ivan Šandrk, 2017/01/09 20:25:54]

I'll think of something else here. Can I just put everything in one level, ie.
public_session_permissions_user_choice_cache?

[gab, 2017/01/09 20:47:01]

Top-level isn't done often either, maybe extensions.?

[Devlin, 2017/01/09 21:22:41]

You could store this in ExtensionPrefs, which is the extensions layer on top of
the profile prefs and maps to extensions.*.

[Ivan Šandrk, 2017/01/11 17:41:50]

Thanks for the suggestion devlin. I'll keep it this way unless that's better for
some reason I'm unaware of.

I'm also planning on doing a bigger refactoring anyway, so it shouldn't matter
too much.

[Ivan Šandrk, 2017/01/11 17:41:51]

I hope this one sounds ok.

[gab, 2017/01/11 19:13:33]

If that's where all extensions.* prefs are then that's probably better but I'll
defer to devlin on that one since this pref_names.cc already has a few
extensions.* prefs.

+
 #endif  // defined(OS_CHROMEOS)
 
 // Whether there is a Flash version installed that supports clearing LSO data.
 const char kClearPluginLSODataEnabled[] = "browser.clear_lso_data_enabled";
 
 // Whether we should show Pepper Flash-specific settings.
 const char kPepperFlashSettingsEnabled[] =
     "browser.pepper_flash_settings_enabled";
 
 // String which specifies where to store the disk cache.
@@ skipping 433 matching lines @@
 const char kSearchGeolocationPreDisclosureMetricsRecorded[] =
     "search_geolocation_pre_disclosure_metrics_recorded";
 
 // Whether the metrics for the state of geolocation post-disclosure being shown
 // have been recorded.
 const char kSearchGeolocationPostDisclosureMetricsRecorded[] =
     "search_geolocation_post_disclosure_metrics_recorded";
 #endif
 
 }  // namespace prefs