Fix a handful of typos (closure->block) to avoid confusion.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@55768 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index b84b958..2264bca 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -1768,7 +1768,7 @@
 //===----------------------------------------------------------------------===//
 
 /// typesAreBlockCompatible - This routine is called when comparing two
-/// closure types. Types must be strictly compatible here.
+/// block types. Types must be strictly compatible here.
 bool ASTContext::typesAreBlockCompatible(QualType lhs, QualType rhs) {
   if (lhs.getCVRQualifiers() != rhs.getCVRQualifiers())
     return false;