fix: Detailslist is still tabbable when isHeaderVisible=false

[smhigley]

Fixes 15391

Adds tabindex="0" to the first row if isHeaderVisible=false is set on the parent DetailsList. This ensures tab focus will always enter the DetailsList, and go to the correct element if there is no header (normally it lands on the first header cell).

FocusZone takes care of tabindex & arrow key behavior after the first time tab enters the DetailsList.

[size-auditor]

Asset size changes

Project	Bundle	Baseline Size	New Size	Difference
office-ui-fabric-react	fluentui-react-DetailsList	222.021 kB	222.059 kB	38 bytes
office-ui-fabric-react	fluentui-react-ShimmeredDetailsList	232.512 kB	232.55 kB	38 bytes

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

Baseline commit: 32fbe9eaa57c09bbf359e0c7de483ed89694adfc (build)

[codesandbox-ci]

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Latest deployment of this branch, based on commit b75ff17:

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

[fabricteam]

📊 Bundle size report

_{🤖 This report was generated against 32fbe9eaa57c09bbf359e0c7de483ed89694adfc}

[fabricteam]

Perf Analysis (@fluentui/react)

No significant results to display.

All results

Scenario	Render type	Master Ticks	PR Ticks	Iterations	Status
BaseButton	mount	1200	1153	5000
Breadcrumb	mount	2967	2923	1000
Checkbox	mount	2602	2659	5000
CheckboxBase	mount	2329	2317	5000
ChoiceGroup	mount	4384	4234	5000
ComboBox	mount	1241	1259	1000
CommandBar	mount	9514	9596	1000
ContextualMenu	mount	10972	11006	1000
DefaultButton	mount	1370	1243	5000
DetailsRow	mount	3292	3514	5000
DetailsRowFast	mount	3630	3545	5000
DetailsRowNoStyles	mount	3300	3484	5000
Dialog	mount	2969	3010	1000
DocumentCardTitle	mount	580	540	1000
Dropdown	mount	3223	3215	5000
FocusTrapZone	mount	1993	1995	5000
FocusZone	mount	1968	1946	5000
GroupedList	mount	52999	57392	2
GroupedList	virtual-rerender	24906	24903	2
GroupedList	virtual-rerender-with-unmount	92055	93448	2
GroupedListV2	mount	566	567	2
GroupedListV2	virtual-rerender	539	538	2
GroupedListV2	virtual-rerender-with-unmount	559	548	2
IconButton	mount	1854	1917	5000
Label	mount	716	721	5000
Layer	mount	4175	4232	5000
Link	mount	828	821	5000
MenuButton	mount	1707	1669	5000
MessageBar	mount	2412	2351	5000
Nav	mount	3282	3228	1000
OverflowSet	mount	1344	1375	5000
Panel	mount	2530	2496	1000
Persona	mount	1314	1239	1000
Pivot	mount	1628	1638	1000
PrimaryButton	mount	1508	1475	5000
Rating	mount	6958	6977	5000
SearchBox	mount	1524	1390	5000
Shimmer	mount	2822	2842	5000
Slider	mount	2081	2081	5000
SpinButton	mount	4659	4678	5000
Spinner	mount	799	750	5000
SplitButton	mount	2990	3099	5000
Stack	mount	840	860	5000
StackWithIntrinsicChildren	mount	2309	2351	5000
StackWithTextChildren	mount	4815	4707	5000
SwatchColorPicker	mount	10543	10149	5000
TagPicker	mount	2600	2535	5000
TeachingBubble	mount	88418	87454	5000
Text	mount	784	795	5000
TextField	mount	1595	1585	5000
ThemeProvider	mount	1520	1525	5000
ThemeProvider	virtual-rerender	1079	1096	5000
ThemeProvider	virtual-rerender-with-unmount	2157	2147	5000
Toggle	mount	1092	1109	5000
buttonNative	mount	548	548	5000