https://bugs.webkit.org/show_bug.cgi?id=125855

Reviewed by Mario Sanchez Prada.

Source/WebCore:

Test: accessibility/aria-checked-mixed-value.html

Expose ATK_STATE_INDETERMINATE to support aria-checked mixed state
for radio and checkbox types.

* accessibility/atk/WebKitAccessibleWrapperAtk.cpp:
(setAtkStateSetFromCoreObject):

Tools:

Added new function isIndeterminate for testing aria-checked mixed state.
I provided respective, but empty function in mac port. Mac testing it differently.

* DumpRenderTree/AccessibilityUIElement.cpp:
(getIsIndeterminate):
(AccessibilityUIElement::getJSClass):
* DumpRenderTree/AccessibilityUIElement.h:
* DumpRenderTree/atk/AccessibilityUIElementAtk.cpp:
(AccessibilityUIElement::isIndeterminate):
* DumpRenderTree/ios/AccessibilityUIElementIOS.mm: Added empty function.
(AccessibilityUIElement::isIndeterminate):
* DumpRenderTree/mac/AccessibilityUIElementMac.mm: Added empty function.
(AccessibilityUIElement::isIndeterminate):
* DumpRenderTree/win/AccessibilityUIElementWin.cpp: Added empty function.
(AccessibilityUIElement::isIndeterminate):
* WebKitTestRunner/InjectedBundle/AccessibilityUIElement.h:
* WebKitTestRunner/InjectedBundle/Bindings/AccessibilityUIElement.idl:
* WebKitTestRunner/InjectedBundle/atk/AccessibilityUIElementAtk.cpp:
(WTR::AccessibilityUIElement::isIndeterminate):
* WebKitTestRunner/InjectedBundle/mac/AccessibilityUIElementMac.mm:
(WTR::AccessibilityUIElement::isIndeterminate):

LayoutTests:

* accessibility/aria-checked-mixed-value-expected.txt: Added.
* accessibility/aria-checked-mixed-value.html: Added.
* platform/mac/TestExpectations: Skipped it, missing implementation.
* platform/win/TestExpectations: Skipped it, missing implementation.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@161417 268f45cc-cd09-0410-ab3c-d52691b4dbfc