Cherry-pick 3839864. rdar://117215059

    AX: Sometimes unable to see play/pause animation context menu item when setting is toggled
    https://bugs.webkit.org/show_bug.cgi?id=263735
    rdar://117215059

    Reviewed by Tyler Wilcock.

    When deciding whether to add the "Play/Pause all animations" or "Play/Pause animation" context menu item, we had previously
    used a softlink to reference _AXSReduceMotionAutoplayAnimatedImagesEnabled. The issue with using this from the web content
    process, however, is that distributed notifications are not permitted as per the sandbox, so updates to this setting were
    not reaching that process.

    To resolve this, this patch now piggybacks onto our existing cross-process update for the animation setting using the
    AccessibilityPreferencesChanged notification and WebPage::updateImageAnimationEnabled. A new flag, m_systemAllowsAnimationControls,
    now maintains the state of this setting, and allows the Page to have an up-to-date view of the setting without relying on the
    softlink.

    * Source/WebCore/page/ContextMenuController.cpp:
    (WebCore::ContextMenuController::populate):
    * Source/WebCore/page/Page.cpp:
    (WebCore::Page::setSystemAllowsAnimationControls):
    * Source/WebCore/page/Page.h:
    (WebCore::Page::systemAllowsAnimationControls const):
    * Source/WebKit/WebProcess/WebPage/WebPage.cpp:
    (WebKit::WebPage::updateImageAnimationEnabled):

    Canonical link: https://commits.webkit.org/269878@main

Identifier: 267815.551@safari-7617.1.17.12-branch

Source/WebCore/page/ContextMenuController.cpp

@@ -95,12 +95,6 @@
 #include <wtf/cocoa/RuntimeApplicationChecksCocoa.h>
 #endif
 
-#if ENABLE(ACCESSIBILITY_ANIMATION_CONTROL)
-#include <wtf/SoftLinking.h>
-SOFT_LINK_LIBRARY_OPTIONAL(libAccessibility)
-SOFT_LINK_OPTIONAL(libAccessibility, _AXSReduceMotionAutoplayAnimatedImagesEnabled, Boolean, (), ());
-#endif
-
 namespace WebCore {
 
 using namespace WTF::Unicode;
@@ -1044,10 +1038,7 @@ void ContextMenuController::populate()
         if (!frame->page() || !frame->page()->settings().imageAnimationControlEnabled())
             return false;
 
-        auto* autoplayAnimatedImagesFunction = _AXSReduceMotionAutoplayAnimatedImagesEnabledPtr();
-        // Only show these controls if autoplay of animated images has been disabled.
-        bool systemAllowsAnimationControls = autoplayAnimatedImagesFunction && !autoplayAnimatedImagesFunction();
-        return systemAllowsAnimationControls || frame->page()->settings().allowAnimationControlsOverride();
+        return frame->page()->systemAllowsAnimationControls() || frame->page()->settings().allowAnimationControlsOverride();
     };
 
     bool shouldAddPlayAllPauseAllAnimationsItem = canAddAnimationControls();

Source/WebCore/page/Page.cpp

@@ -2179,7 +2179,12 @@ void Page::setImageAnimationEnabled(bool enabled)
     updatePlayStateForAllAnimations();
     chrome().client().isAnyAnimationAllowedToPlayDidChange(enabled);
 }
-#endif
+
+void Page::setSystemAllowsAnimationControls(bool isAllowed)
+{
+    m_systemAllowsAnimationControls = isAllowed;
+}
+#endif // ENABLE(ACCESSIBILITY_ANIMATION_CONTROL)
 
 void Page::suspendScriptedAnimations()
 {

Source/WebCore/page/Page.h

@@ -697,10 +697,12 @@ class Page : public Supplementable<Page>, public CanMakeWeakPtr<Page> {
 #if ENABLE(ACCESSIBILITY_ANIMATION_CONTROL)
     void updatePlayStateForAllAnimations();
     WEBCORE_EXPORT void setImageAnimationEnabled(bool);
+    WEBCORE_EXPORT void setSystemAllowsAnimationControls(bool isAllowed);
     void addIndividuallyPlayingAnimationElement(HTMLImageElement&);
     void removeIndividuallyPlayingAnimationElement(HTMLImageElement&);
 #endif
     bool imageAnimationEnabled() const { return m_imageAnimationEnabled; }
+    bool systemAllowsAnimationControls() const { return m_systemAllowsAnimationControls; }
 
     void userStyleSheetLocationChanged();
     const String& userStyleSheet() const;
@@ -1225,6 +1227,7 @@ class Page : public Supplementable<Page>, public CanMakeWeakPtr<Page> {
 
     bool m_canStartMedia { true };
     bool m_imageAnimationEnabled { true };
+    bool m_systemAllowsAnimationControls { false };
     // Elements containing animations that are individually playing (potentially overriding the page-wide m_imageAnimationEnabled state).
     WeakHashSet<HTMLImageElement, WeakPtrImplWithEventTargetData> m_individuallyPlayingAnimationElements;
 

Source/WebKit/WebProcess/WebPage/WebPage.cpp

@@ -8783,6 +8783,7 @@ void WebPage::generateTestReport(String&& message, String&& group)
 void WebPage::updateImageAnimationEnabled()
 {
     corePage()->setImageAnimationEnabled(WebProcess::singleton().imageAnimationEnabled());
+    corePage()->setSystemAllowsAnimationControls(!WebProcess::singleton().imageAnimationEnabled());
 }
 
 void WebPage::pauseAllAnimations(CompletionHandler<void()>&& completionHandler)