Remove an assertion that is not valid if we cancel parsing.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@145108 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/Preprocessor.cpp b/lib/Lex/Preprocessor.cpp
index af0faca..798244c 100644
--- a/lib/Lex/Preprocessor.cpp
+++ b/lib/Lex/Preprocessor.cpp
@@ -74,9 +74,6 @@
 
 Preprocessor::~Preprocessor() {
   assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!");
-  assert(((MacroExpandingLexersStack.empty() && MacroExpandedTokens.empty()) ||
-          isCodeCompletionReached()) &&
-         "Preprocessor::HandleEndOfTokenLexer should have cleared those");
 
   while (!IncludeMacroStack.empty()) {
     delete IncludeMacroStack.back().TheLexer;