Remove status bar item flickering

[fcollonval]

References

Fix #9910
It is part of performance improvement as this reduces the items displacement flagged by Chrome.

Code changes

Set more appropriately isActive on status bar items.

User-facing changes

No more flickering of the status bar items (except from kernel status changes)

Backwards-incompatible changes

N/A

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Benchmark report

The execution time (in milliseconds) are grouped by test file, test type and browser.
For each case, the following values are computed: min <- [1st quartile - median - 3rd quartile] -> max.

Results table

Test file	large_code_notebook	large_md_notebook
open
chromium
actual	6402 <- [7283 - 7333 - 7614] -> 8060	3374 <- [3408 - 3450 - 3563] -> 3741
expected	6938 <- [7584 - 7618 - 7760] -> 8204	3461 <- [3524 - 3534 - 3590] -> 4136
switch-from
chromium
actual	410 <- [437 - 456 - 462] -> 514	300 <- [308 - 312 - 330] -> 391
expected	464 <- [480 - 489 - 499] -> 789	310 <- [338 - 344 - 352] -> 370
switch-to
chromium
actual	1671 <- [1698 - 1717 - 1736] -> 1809	1448 <- [1484 - 1501 - 1518] -> 1574
expected	1706 <- [1730 - 1764 - 1814] -> 2015	1541 <- [1549 - 1562 - 1574] -> 1608
close
chromium
actual	5197 <- [5542 - 8901 - 14012] -> 15830	3521 <- [3678 - 3784 - 3958] -> 4237
expected	5176 <- [5770 - 10533 - 14493] -> 18824	3325 <- [3691 - 3890 - 3939] -> 4073

❗ Test metadata have changed

--- /dev/fd/63	2021-09-13 12:27:23.123445996 +0000
+++ /dev/fd/62	2021-09-13 12:27:23.123445996 +0000
@@ -34,7 +34,7 @@
       "voltage": ""
     },
     "mem": {
-      "total": 7291699200
+      "total": 7291695104
     },
     "osInfo": {
       "arch": "x64",
@@ -46,7 +46,7 @@
       "logofile": "ubuntu",
       "platform": "linux",
       "release": "20.04.3 LTS",
-      "serial": "cfc067bfcb844f35865e279a1b0e66c5",
+      "serial": "0f5fd491ff264b5f9d56e03599b4fae0",
       "servicepack": "",
       "uefi": false
     }

[blink1073]

Thank you!

[blink1073]

@meeseeksdev please backport to 3.1.x