[Xcode] Stop passing -fvisibility-inlines-hidden to TAPI

https://bugs.webkit.org/show_bug.cgi?id=264108
rdar://116350284

Reviewed by Alexey Proskuryakov.

It is unrecognized in recent toolchains, and does not appear to be
needed. WebKitLegacy doesn't have any inlined declarations in
public/private headers.

* Source/WebKitLegacy/mac/Configurations/WebKitLegacy.xcconfig:

Canonical link: https://commits.webkit.org/270147@main

Source/JavaScriptCore/Configurations/JavaScriptCore.xcconfig

@@ -46,7 +46,9 @@ TAPI_USE_SRCROOT = $(TAPI_USE_SRCROOT$(WK_XCODE_15));
 TAPI_USE_SRCROOT_XCODE_SINCE_15 = YES;
 TAPI_ENABLE_PROJECT_HEADERS = YES;
 TAPI_VERIFY_MODE = Pedantic;
-// C++ dialect flags (-std, -fvisibility, -fno-rtti) are needed because JavaScriptCore / WTF private headers are only safe to use from other WebKit projects, which build with the same dialect.
+// C++ dialect flags (-fvisibility, others inherited from CommonBase.xcconfig)
+// are needed because JavaScriptCore / WTF private headers are only safe to use
+// from other WebKit projects, which build with the same dialect.
 OTHER_TAPI_FLAGS = $(inherited) -fvisibility=hidden -exclude-private-header **/*SPI.h -extra-project-header $(SRCROOT)/API/ExtraSymbolsForTAPI.h $(OTHER_TAPI_FLAGS_STATICLIBS_$(DEPLOYMENT_LOCATION));
 // JavaScriptCore exports libWTF.a and libbmalloc.a, so tapi needs to know about headers from those projects. The extra filelists are generated by their respective projects. In install-style builds, there is a postprocessing step done as a JavaScriptCore build phase.
 OTHER_TAPI_FLAGS_STATICLIBS_NO = -filelist $(BUILT_PRODUCTS_DIR)/usr/local/include/bmalloc/bmalloc.json -filelist $(BUILT_PRODUCTS_DIR)/usr/local/include/wtf/WTF.json

Source/WebKitLegacy/mac/Configurations/WebKitLegacy.xcconfig

@@ -117,7 +117,7 @@ TAPI_USE_SRCROOT_XCODE_SINCE_15 = YES;
 TAPI_VERIFY_MODE = Pedantic;
 
 // FIXME: Replace -extra-*-header and -exclude-*-header flags with build setting equivalents once rdar://99885053 is completed in all needed toolchains.
-OTHER_TAPI_FLAGS = $(inherited) -fvisibility-inlines-hidden $(WK_CFLAGS_BUILD_FOR_TESTING_$(WK_BUILD_FOR_TESTING)) -DRELEASE_WITHOUT_OPTIMIZATIONS -exclude-private-header $(BUILT_PRODUCTS_DIR)/$(PRIVATE_HEADERS_FOLDER_PATH)/NSURLDownloadSPI.h -extra-private-header $(SOURCE_ROOT)/mac/TestingFunctions.h -extra-private-header $(SOURCE_ROOT)/mac/ExtraPrivateSymbolsForTAPI.h $(OTHER_TAPI_FLAGS_SRCROOT_$(TAPI_USE_SRCROOT));
+OTHER_TAPI_FLAGS = $(inherited) $(WK_CFLAGS_BUILD_FOR_TESTING_$(WK_BUILD_FOR_TESTING)) -DRELEASE_WITHOUT_OPTIMIZATIONS -exclude-private-header $(BUILT_PRODUCTS_DIR)/$(PRIVATE_HEADERS_FOLDER_PATH)/NSURLDownloadSPI.h -extra-private-header $(SOURCE_ROOT)/mac/TestingFunctions.h -extra-private-header $(SOURCE_ROOT)/mac/ExtraPrivateSymbolsForTAPI.h $(OTHER_TAPI_FLAGS_SRCROOT_$(TAPI_USE_SRCROOT));
 // Include WebKitPrefix.h to work around rdar://104248994.
 OTHER_TAPI_FLAGS_SRCROOT_YES = -Xparser -include -Xparser mac/WebKitPrefix.h $(OTHER_TAPI_FLAGS_102197642_WORKAROUND);