- Add 'CurPPLexer' to Preprocessor to keep track of the current
  PreprocessorLexer, which will either be a 'Lexer' or 'PTHLexer'.
- Added stub field 'CurPTHLexer' to keep track of the current PTHLexer.
- Modified IncludeStackInfo to track both the current PTHLexer and
  current PreprocessorLexer.

llvm-svn: 59472
diff --git a/clang/lib/Lex/PPLexerChange.cpp b/clang/lib/Lex/PPLexerChange.cpp
index 0b2211b..3b63c9b 100644
--- a/clang/lib/Lex/PPLexerChange.cpp
+++ b/clang/lib/Lex/PPLexerChange.cpp
@@ -89,6 +89,7 @@
     PushIncludeMacroStack();
 
   CurLexer.reset(TheLexer);
+  CurPPLexer = TheLexer;
   CurDirLookup = CurDir;
   
   // Notify the client, if desired, that we are in a new source file.