Add specs for issue 1612

This PR add specs for sass/libsass#1612

Author: xzyfer

spec/libsass-todo-issues/issue_1612/expected.compact.css

@@ -0,0 +1 @@
+c { b: "foo", bar; b: "foo", bar; }

spec/libsass-todo-issues/issue_1612/expected.compressed.css

@@ -0,0 +1 @@
+c{b:"foo", bar;b:"foo",bar}

spec/libsass-todo-issues/issue_1612/expected.expanded.css

@@ -0,0 +1,4 @@
+c {
+  b: "foo", bar;
+  b: "foo", bar;
+}

spec/libsass-todo-issues/issue_1612/expected_output.css

@@ -0,0 +1,3 @@
+c {
+  b: "foo", bar;
+  b: "foo", bar; }

spec/libsass-todo-issues/issue_1612/input.scss

@@ -0,0 +1,4 @@
+c {
+  b: "foo", bar;
+  b: "foo", bar
+}