Use SmallVectorImpl instead of SmallVector for iterators and references to avoid specifying the vector size unnecessarily.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@185610 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index bf01e9c..b9061ad 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -3120,7 +3120,7 @@
     // Only emit declarations that aren't from a chained PCH, though.
     SmallVector<Decl *, 16> Decls(IdResolver.begin(II),
                                   IdResolver.end());
-    for (SmallVector<Decl *, 16>::reverse_iterator D = Decls.rbegin(),
+    for (SmallVectorImpl<Decl *>::reverse_iterator D = Decls.rbegin(),
                                                 DEnd = Decls.rend();
          D != DEnd; ++D)
       clang::io::Emit32(Out, Writer.getDeclID(getMostRecentLocalDecl(*D)));
@@ -4022,7 +4022,7 @@
 
   // Make sure visible decls, added to DeclContexts previously loaded from
   // an AST file, are registered for serialization.
-  for (SmallVector<const Decl *, 16>::iterator
+  for (SmallVectorImpl<const Decl *>::iterator
          I = UpdatingVisibleDecls.begin(),
          E = UpdatingVisibleDecls.end(); I != E; ++I) {
     GetDeclRef(*I);
@@ -4296,8 +4296,8 @@
     return;
 
   RecordData Record;
-  for (SmallVector<ReplacedDeclInfo, 16>::iterator
-           I = ReplacedDecls.begin(), E = ReplacedDecls.end(); I != E; ++I) {
+  for (SmallVectorImpl<ReplacedDeclInfo>::iterator
+         I = ReplacedDecls.begin(), E = ReplacedDecls.end(); I != E; ++I) {
     Record.push_back(I->ID);
     Record.push_back(I->Offset);
     Record.push_back(I->Loc);