[ODRHash] Stop hashing `ObjCMethodDecl::isPropertyAccessor` as it doesn't capture inherent method quality.

[vsapsai]

Summary

isPropertyAccessor depends on the surrounding code and not on the method
itself. That's why it can be different in different modules. And
mismatches shouldn't be an error.

rdar://109481753

clang/lib/AST/ODRHash.cpp

void VisitCXXMethodDecl(const CXXMethodDecl *D) {
     // Handled by the ODRHash for FunctionDecl
 
     Inherited::VisitCXXMethodDecl(D);
   }
 
   void VisitObjCMethodDecl(const ObjCMethodDecl *Method) {
     ID.AddInteger(Method->getDeclKind());
     Hash.AddBoolean(Method->isInstanceMethod()); // false if class method
-    Hash.AddBoolean(Method->isPropertyAccessor());
     Hash.AddBoolean(Method->isVariadic());
     Hash.AddBoolean(Method->isSynthesizedAccessorStub());
     Hash.AddBoolean(Method->isDefined());
     Hash.AddBoolean(Method->isDirectMethod());
     Hash.AddBoolean(Method->isThisDeclarationADesignatedInitializer());
     Hash.AddBoolean(Method->hasSkippedBody());
 
     ID.AddInteger(Method->getImplementationControl());

clang/test/Modules/compare-objc-nonisolated-methods.m

 // RUN: rm -rf %t
 // RUN: split-file %s %t
 
 // Test that different values of `ObjCMethodDecl::isOverriding` in different modules
 // is not an error because it depends on the surrounding code and not on the method itself.
 // RUN: %clang_cc1 -fsyntax-only -verify -I%t/include -fmodules -fimplicit-module-maps -fmodules-cache-path=%t/modules.cache -fmodule-name=Override %t/test-overriding.m
 
+// Test that different values of `ObjCMethodDecl::isPropertyAccessor` in different modules
+// is not an error because it depends on the surrounding code and not on the method itself.
+// RUN: %clang_cc1 -fsyntax-only -verify -I%t/include -fmodules -fimplicit-module-maps -fmodules-cache-path=%t/modules.cache -fmodule-name=PropertyAccessor %t/test-property_accessor.m
+
 //--- include/Common.h
 @interface NSObject
 @end
 
 //--- include/Indirection.h
 #import <Override.h>
+#import <PropertyAccessor.h>
 
 //--- include/module.modulemap
 module Common {
   header "Common.h"
   export *
 }
 module Indirection {
   header "Indirection.h"
   export *
 }
 module Override {
   header "Override.h"
   export *
 }
+module PropertyAccessor {
+  header "PropertyAccessor.h"
+  export *
+}
 
 //--- include/Override.h
 #import <Common.h>
 @interface SubClass: NSObject
 - (void)potentialOverride;
 @end
 
 //--- Override_Internal.h

 
 // Get modular version of `SubClass` where `-[SubClass potentialOverride]` is
 // not an override because module "Override" doesn't know about Override_Internal.h.
 #import <Indirection.h>
 
 void triggerOverrideCheck(SubClass *sc) {
   [sc potentialOverride];
 }
+
+//--- include/PropertyAccessor.h
+#import <Common.h>
+@interface PropertySubClass: NSObject
+- (int)potentialProperty;
+- (void)setPotentialProperty:(int)p;
+@end
+
+//--- PropertyAccessor_Internal.h
+#import <PropertyAccessor.h>
+@interface PropertySubClass()
+@property int potentialProperty;
+@end
+
+//--- test-property_accessor.m
+//expected-no-diagnostics
+// Get a version of `PropertySubClass` where `-[PropertySubClass potentialProperty]`
+// is a property accessor.
+#import "PropertyAccessor_Internal.h"
+
+// Get a version of `PropertySubClass` where `-[PropertySubClass potentialProperty]`
+// is not a property accessor because module "PropertyAccessor" doesn't know about PropertyAccessor_Internal.h.
+#import <Indirection.h>
+
+void triggerPropertyAccessorCheck(PropertySubClass *x) {
+  int tmp = [x potentialProperty];
+  [x setPotentialProperty: tmp];
+}