ASTUnit: Constant fold UseBumpAllocator to true, we don't care to support this as an argument.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@96316 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/ASTMerge.cpp b/lib/Frontend/ASTMerge.cpp
index 3f74e42..2228ea4 100644
--- a/lib/Frontend/ASTMerge.cpp
+++ b/lib/Frontend/ASTMerge.cpp
@@ -38,7 +38,7 @@
                                        &CI.getASTContext());
   for (unsigned I = 0, N = ASTFiles.size(); I != N; ++I) {
     ASTUnit *Unit = ASTUnit::LoadFromPCHFile(ASTFiles[I], CI.getDiagnostics(),
-                                             false, true);
+                                             false);
     if (!Unit)
       continue;