Don't treat 'import' as a contextual keyword when we're in a caching lexer, or when modules are disabled.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147524 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PPCaching.cpp b/lib/Lex/PPCaching.cpp
index 986341b..0d5e34f 100644
--- a/lib/Lex/PPCaching.cpp
+++ b/lib/Lex/PPCaching.cpp
@@ -42,6 +42,7 @@
          && "EnableBacktrackAtThisPos was not called!");
   CachedLexPos = BacktrackPositions.back();
   BacktrackPositions.pop_back();
+  recomputeCurLexerKind();
 }
 
 void Preprocessor::CachingLex(Token &Result) {
@@ -74,8 +75,7 @@
     return;
 
   PushIncludeMacroStack();
-  if (CurLexerKind != CLK_LexAfterModuleImport)
-    CurLexerKind = CLK_CachingLexer;
+  CurLexerKind = CLK_CachingLexer;
 }