Un-revert r156142, "[libclang] Bring back BodyIndexer::TraverseCXXOperatorCallExpr".

It was reverted on r156253.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156330 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/libclang/IndexBody.cpp b/tools/libclang/IndexBody.cpp
index 26ec7d1..e1b9f2a 100644
--- a/tools/libclang/IndexBody.cpp
+++ b/tools/libclang/IndexBody.cpp
@@ -117,6 +117,12 @@
     return true;
   }
 
+  bool TraverseCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
+    if (E->getOperatorLoc().isInvalid())
+      return true; // implicit.
+    return base::TraverseCXXOperatorCallExpr(E);
+  }
+
   bool VisitDeclStmt(DeclStmt *S) {
     if (IndexCtx.shouldIndexFunctionLocalSymbols())
       IndexCtx.indexDeclGroupRef(S->getDeclGroup());