Fix clang-tidy patterns to adapt to newly added ExprWithCleanups nodes.

Summary: This is a fix for the new ExprWithCleanups introduced by clang's temporary variable lifetime marks change.

Reviewers: bkramer, sbenza, angelgarcia, alexth

Subscribers: rsmith, cfe-commits

Differential Revision: http://reviews.llvm.org/D21243

llvm-svn: 273310
diff --git a/clang-tools-extra/clang-tidy/modernize/UseAutoCheck.cpp b/clang-tools-extra/clang-tidy/modernize/UseAutoCheck.cpp
index 1f1c140..8c43e6b 100644
--- a/clang-tools-extra/clang-tidy/modernize/UseAutoCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/UseAutoCheck.cpp
@@ -42,6 +42,8 @@
   if (!Init)
     return false;
 
+  Init = Init->IgnoreImplicit();
+
   // The following test is based on DeclPrinter::VisitVarDecl() to find if an
   // initializer is implicit or not.
   if (const auto *Construct = dyn_cast<CXXConstructExpr>(Init)) {