Fix some grammar nits in the comments from Nick.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@133571 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 1b9fd77..92da37b 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -1857,7 +1857,7 @@
   return false;
 }
 
-/// \brief If E is a sizeof expression returns the argument expression,
+/// \brief If E is a sizeof expression, returns its argument expression,
 /// otherwise returns NULL.
 static const Expr *getSizeOfExprArg(const Expr* E) {
   if (const UnaryExprOrTypeTraitExpr *SizeOf =
@@ -1868,7 +1868,7 @@
   return 0;
 }
 
-/// \brief If E is a sizeof expression returns the argument type.
+/// \brief If E is a sizeof expression, returns its argument type.
 static QualType getSizeOfArgType(const Expr* E) {
   if (const UnaryExprOrTypeTraitExpr *SizeOf =
       dyn_cast<UnaryExprOrTypeTraitExpr>(E))