Add option to switch off putting header modules into the dependency file.

llvm-svn: 232721
diff --git a/clang/test/Driver/pch-deps.c b/clang/test/Driver/pch-deps.c
index 3048636..2c140e5 100644
--- a/clang/test/Driver/pch-deps.c
+++ b/clang/test/Driver/pch-deps.c
@@ -8,3 +8,14 @@
 // RUN: FileCheck %s -check-prefix=CHECK-NOPCH -input-file=%t
 // CHECK-NOPCH: -dependency-file
 // CHECK-NOPCH-NOT: -module-file-deps
+
+// RUN: %clang -x c-header %s -o %t.pch -MMD -MT dependencies -MF %t.d \
+// RUN:     -fno-module-file-deps -### 2> %t
+// RUN: FileCheck %s -check-prefix=CHECK-EXPLICIT -input-file=%t
+// CHECK-EXPLICIT: -dependency-file
+// CHECK-EXPLICIT-NOT: -module-file-deps
+
+// RUN: %clang -x c++ %s -o %t.o -MMD -MT dependencies -MF %t.d -fmodule-file-deps -### 2> %t
+// RUN: FileCheck %s -check-prefix=CHECK-EXPLICIT-NOPCH -input-file=%t
+// CHECK-EXPLICIT-NOPCH: -dependency-file
+// CHECK-EXPLICIT-NOPCH: -module-file-deps