patch 8.0.0148: wrong indent in C preprocessor with line continuation

Problem:    When a C preprocessor statement has two line continuations the
            following line does not have the right indent. (Ken Takata)
Solution:   Add the indent of the previous continuation line. (Hirohito
            Higashi)
diff --git a/src/testdir/test3.in b/src/testdir/test3.in
index 096f152..e8648d3 100644
--- a/src/testdir/test3.in
+++ b/src/testdir/test3.in
Binary files differ