Start implementing support for @synchonized with the darwin ObjC API.

Patch by Fariborz!



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@59377 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGObjCRuntime.h b/lib/CodeGen/CGObjCRuntime.h
index d690289..435e148 100644
--- a/lib/CodeGen/CGObjCRuntime.h
+++ b/lib/CodeGen/CGObjCRuntime.h
@@ -38,6 +38,7 @@
 
   class ObjCAtTryStmt;
   class ObjCAtThrowStmt;
+  class ObjCAtSynchronizedStmt;
   class ObjCCategoryImplDecl;
   class ObjCImplementationDecl;
   class ObjCInterfaceDecl;
@@ -142,6 +143,8 @@
                            const ObjCAtTryStmt &S) = 0;
   virtual void EmitThrowStmt(CodeGen::CodeGenFunction &CGF,
                              const ObjCAtThrowStmt &S) = 0;
+  virtual void EmitSynchronizedStmt(CodeGen::CodeGenFunction &CGF,
+                                    const ObjCAtSynchronizedStmt &S) = 0;
 };
 
 /// Creates an instance of an Objective-C runtime class.