[objective-c/c++, testsuite, 1/3] Workaround for PR90709.

[objective-c/c++, testsuite, 1/3] Workaround for PR90709.

Since we cannot parse the current NeXT headers, because of PR90709 and its
dependents, we have a large amount of testsuite noise for Darwin platforms.
In order to restore the usefulness of the testsuite, we are going add headers
without the modern syntax elements that trigger the bug, and use these for
test runs on newer Darwin.

The headers are imported from GNUStep, with some local modifications to make
sure that __BLOCKS__ is honoured as a gate for Apple-style blocks closures.

CF-CFString.h, F-NS*.h are proxy headers that use the installed CoreFoundation
or Foundation headers on systems <= Darwin12 and the GNUStep headers for newer.

2019-06-15  Iain Sandoe  <iain@sandoe.co.uk>

	PR objc/90709
	* objc-obj-c++-shared/CF-CFString.h: New.
	* objc-obj-c++-shared/F-NSArray.h: New.
	* objc-obj-c++-shared/F-NSAutoreleasePool.h: New.
	* objc-obj-c++-shared/F-NSObject.h: New.
	* objc-obj-c++-shared/F-NSString.h: New.
	* objc-obj-c++-shared/F-NSValue.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFArray.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFAvailability.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFBase.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFCharacterSet.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFData.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFDictionary.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFLocale.h: New.
	* objc-obj-c++-shared/GNUStep/CoreFoundation/CFString.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSArray.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSAutoreleasePool.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSDate.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSEnumerator.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSGeometry.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSObjCRuntime.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSObject.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSRange.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSString.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSValue.h: New.
	* objc-obj-c++-shared/GNUStep/Foundation/NSZone.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/GNUstep.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/GSBlocks.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/GSConfig.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/GSObjCRuntime.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/GSVersionMacros.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/NSArray+GNUstepBase.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/NSMutableString+GNUstepBase.h:
	New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/NSNumber+GNUstepBase.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/NSObject+GNUstepBase.h: New.
	* objc-obj-c++-shared/GNUStep/GNUstepBase/NSString+GNUstepBase.h: New.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@272325 138bc75d-0d04-0410-961f-82ee72b054a4