feat(Stack): Add deprecated flag to render null when receiving a falsy value

[sopranopillow]

Previous Behavior

After #25685, we no longer render null when receiving a falsy value in Stack. Instead, we render the actual child.

New Behavior

We keep the same behavior, but allow the previous behavior under a doNotRenderFalsyValues prop.

Related Issue(s)

• Fixes [Bug]: Stack in @fluentui/react version 8.101.2 changed to rendering falsy elements instead of returning null causes zeros to render #28970

[fabricteam]

📊 Bundle size report

_{🤖 This report was generated against 0dfca34f7aabc1ee0c087a1dfcc4d55b6880c883}

[fabricteam]

🕵 fluentuiv8 No visual regressions between this PR and main

[fabricteam]

Perf Analysis (@fluentui/react)

No significant results to display.

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
BaseButton	mount	627	635	5000
Breadcrumb	mount	1668	1635	1000
Checkbox	mount	1684	1692	5000
CheckboxBase	mount	1471	1455	5000
ChoiceGroup	mount	2932	2914	5000
ComboBox	mount	662	656	1000
CommandBar	mount	6117	6058	1000
ContextualMenu	mount	11671	11768	1000
DefaultButton	mount	746	744	5000
DetailsRow	mount	2192	2169	5000
DetailsRowFast	mount	2164	2147	5000
DetailsRowNoStyles	mount	2012	1986	5000
Dialog	mount	2600	2780	1000
DocumentCardTitle	mount	229	220	1000
Dropdown	mount	1944	1967	5000
FocusTrapZone	mount	1100	1096	5000
FocusZone	mount	1047	1029	5000
GroupedList	mount	41114	41138	2
GroupedList	virtual-rerender	17540	19690	2
GroupedList	virtual-rerender-with-unmount	50210	50148	2
GroupedListV2	mount	222	233	2
GroupedListV2	virtual-rerender	208	211	2
GroupedListV2	virtual-rerender-with-unmount	220	229	2
IconButton	mount	1068	1085	5000
Label	mount	335	337	5000
Layer	mount	2687	2726	5000
Link	mount	369	384	5000
MenuButton	mount	932	925	5000
MessageBar	mount	21211	21256	5000
Nav	mount	1904	1921	1000
OverflowSet	mount	758	770	5000
Panel	mount	2008	1770	1000
Persona	mount	733	726	1000
Pivot	mount	863	862	1000
PrimaryButton	mount	852	837	5000
Rating	mount	4573	4546	5000
SearchBox	mount	921	887	5000
Shimmer	mount	1837	1847	5000
Slider	mount	1301	1322	5000
SpinButton	mount	2861	2881	5000
Spinner	mount	381	385	5000
SplitButton	mount	1824	1770	5000
Stack	mount	411	404	5000
StackWithIntrinsicChildren	mount	823	862	5000
StackWithTextChildren	mount	2565	2561	5000
SwatchColorPicker	mount	6139	6187	5000
TagPicker	mount	1466	1491	5000
Text	mount	371	399	5000
TextField	mount	949	958	5000
ThemeProvider	mount	811	824	5000
ThemeProvider	virtual-rerender	577	571	5000
ThemeProvider	virtual-rerender-with-unmount	1260	1263	5000
Toggle	mount	596	604	5000
buttonNative	mount	194	187	5000

[khmakoto]

You probably need to update the API file.

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit d92bbef:

Sandbox	Source
@fluentui/react 8 starter	Configuration
@fluentui/react-components 9 starter	Configuration

[size-auditor]

Asset size changes

Project	Bundle	Baseline Size	New Size	Difference
office-ui-fabric-react	fluentui-react-Stack	40.598 kB	40.75 kB	152 bytes
office-ui-fabric-react	fluentui-react-TeachingBubble	197.526 kB	197.678 kB	152 bytes

 Over Tolerance (1024 B)  Over Baseline  Below Baseline  New   Removed 1 kB = 1000 B

Baseline commit: 0e33d8ebd9aecc1efe0cc664288ec433a8878ff8 (build)