Fix MSVC warning about missing 'this' from lambda default capture mode

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@285281 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Lex/PPLexerChange.cpp

@@ -41,7 +41,7 @@ bool Preprocessor::isInPrimaryFile() const {
   assert(IsFileLexer(IncludeMacroStack[0]) &&
          "Top level include stack isn't our primary lexer?");
   return std::none_of(IncludeMacroStack.begin() + 1, IncludeMacroStack.end(),
-                      [](const IncludeStackInfo &ISI) -> bool {
+                      [this](const IncludeStackInfo &ISI) -> bool {
     return IsFileLexer(ISI);
   });
 }