* Device: Add a `hasSeamlessWifiToggle` devcap to complement `hasWifiToggle`, to denote platforms where we can toggle WiFi without losing focus, as this has obvious UX impacts, and less obvious technical impacts on some of the NetworkMgr innards...
* Android: Mark as `!hasSeamlessWifiToggle`, as it requires losing focus to the system settings. Moreover, `turnOnWifi` returns *immediately* and we *still* run in the background during that time, for extra spiciness...
* NetworkMgr: Ensure only *one* call to `turnOnWifi` will actually go on when stuff gets re-scheduled by the `beforeWifiAction` framework.
* NetworkMgr: Ensure the `beforeWifiAction` framework will not re-schedule the same thing *ad vitam aeternam* if a previous connection attempt is still ongoing. (i.e., previously, on Android, if you backed out of the system settings, you entered the Benny Hill dimension, as NetworkMgr would keep throwing you back into the system settings ;p). This has a few implications on callbacks requested by subsequent connection attempts, though. Generally, we'll try to honor *explicitly interactive* callbacks, but `beforeWifiAction` stuff will be dropped (only the original cb is preserved). That's what prevents the aforementioned infinite loop, as the `beforeWifiAction` framework was based on the assumption that `turnOnWifi` somewhat guaranteed `isConnected` to be true on return, something which is only actually true on `hasWifiManager` platforms.
* NetworkMgr: In `prompt` mode, the above implies that the prompt will not even be shown for concurrent attempts, as it's otherwise extremely confusing (KOSync on Android being a prime example, as it has a pair of Suspend/Resume handlers, so the initial attempt trips those two because of the focus switch >_<").
* NetworkMgr: Don't attempt to kill wifi when aborting a connection attempt on `!hasSeamlessWifiToggle` (because, again, it'll break UX, and also because it might run at very awkward times (e.g., I managed to go back to KOReader *between* a FM/Reader switch at one point, which promptly caused `UIManager` to exit because there was nothing to show ;p).
* NetworkMgr: Don't drop the connectivity callback when `beforeWifiAction` is set to prompt and the target happens to use a connectivity check in its `turnOnWifi` implementation (e.g., on Kindle).
* Android: Add an `"ignore"` `beforeWifiAction` mode, that'll do nothing but schedule the connectivity check with its callback (with the intent being the system will eventually enable wifi on its own Soon(TM)). If you're already online, the callback will run immediately, obviously. If you followed the early discussions on this PR, this closely matches what happens on `!hasWifiToggle` platforms (as flagging Android that way was one of the possible approaches here).
* NetworkMgr: Bail out early in `goOnlineToRun` if `beforeWifiAction` isn't `"turn_on"`. Prompt cannot work there, and while ignore technically could, it would serve very little purpose given its intended use case.
* KOSync: Neuter the Resume/Suspend handlers early on `CloseDocument`, as this is how focus switches are handled on Android, and if `beforeWifiAction` is `turn_on` and you were offline at the time, we'd trip them because of the swap to system settings to enable wifi.
* KOSync: Allow `auto_sync` to be enabled regardless of the `beforeWifiAction` mode on `!hasSeamlessWifiToggle` platforms. Prompt is still a terrible idea, but given that `goOnlineToRun` now aborts early if the mode is not supported, it's less of a problem.
Move as much of the state tracking as possible inside VirtualKeyboard itself.
InputDialog unfortunately needs an internal tracking of this state because it needs to know about it *before* the VK is shown, so we have to keep a bit of duplication in there, although we do try much harder to keep everything in sync (at least at function call edges), and to keep the damage contained to, essentially, the toggle button's handler.
(Followup to #10803 & #10850)
* Enforce a minimal standby timer for the first standby after a resume.
* On Kobo, sleep a bit before standby.
This aims to alleviate race conditions causing visible refresh glitches on sunxi, especially when using an extremely low standby timer (i.e., below the defaults).
An attempt was made in the original code, but the whole thing was designed in the hope of actually switching to turbo, so it was super janky without it.
Anyway, we now actually have a sane way to set socket timeouts, so, use that, and set them very tight for now.
This is fairly critical right now, because the server is down, and the default timeouts are ~30s. That happens to be *above* the debounce threshold, so you can't even hope for that to help you. Meaning, right now, you get a 2 * 30s block on resume with auto sync. That's... Very Not Good(TM).
That becomes a single 2s one after this.
And add an OTM block to do a cleanup pass on existing DBs (which might take a while if you're severely affected, because we've seen reports of DBs north of 2GB).
* Enable before_wifi_action & after_wifi_action on hasWifiToggle platforms (which is basically all of 'em except naked SDL).
* Decouple restoreWifiAsync from hasWifiManger, because we can do that on other platforms (namely, Kindle. Probably PB, too, but WiFi is already a mess there, and I can't test it).
* Implement restoreWifiAsync on Kindle.
* Properly flag rM as hasWifiManager & hasFastWifiStatusQuery, because it is actually both of those (it uses our wpa_supplicant backend).
* Update the KOSync checks to take these changes into account, to properly disable auto_sync if necessary.
* Really made the Network* event signaling consistent. For realz this time.
* In an effort to make the whole beforeWifiAction framework somewhat usable there, we now assume connectivity is always available on !hasWifiToggle platforms...
