Use the expansion location of the file name when finding the module.

The spelling location of stringified strings is not a file location.
Optimally, we'll want to solve the problem (as the FIXME states) by
handing in the right FileEntry of the #include location.

llvm-svn: 204220
diff --git a/clang/test/Modules/Inputs/declare-use/j.h b/clang/test/Modules/Inputs/declare-use/j.h
new file mode 100644
index 0000000..04d46a9
--- /dev/null
+++ b/clang/test/Modules/Inputs/declare-use/j.h
@@ -0,0 +1,14 @@
+#ifndef J_H
+#define J_H
+
+#define STR(x) #x
+#define HDR(x) STR(x.h)
+
+#include ALLOWED_INC
+#include HDR(a)
+
+const int j = a * a + b;
+
+// expected-no-diagnostics
+
+#endif