Add missing test case for previous commit.
# Check whitespace skipping "$\n" handling.
#
# RUN: %{llbuild} ninja lex %s 2> %t.err
# RUN: %{FileCheck} < %t.err %s

# Ninja does *not* recognize '$\n' on a leading line.
# CHECK: (Token "Unknown" String:"$" Length:1 Line:[[@LINE+1]] Column:0)
$

# Check '$\n' in other contexts.
#
# CHECK: (Token "Identifier" String:"a" Length:1 Line:[[@LINE+2]] Column:0)
# CHECK-NEXT: (Token "Equals" String:"=" Length:1 Line:[[@LINE+2]] Column:0)
a$
= b

# CHECK: (Token "Identifier" String:"a" Length:1 Line:[[@LINE+2]] Column:0)
# CHECK-NEXT: (Token "Equals" String:"=" Length:1 Line:[[@LINE+3]] Column:0)
a $
    $
= b