importer: Allow /usr/local RPM content

Obviously, this alone is not enough to expose that content but it's a
start. Currently as is, it'll get nuked when we replace `/usr/local` by
a symlink in postprocessing. A future patch will address that part.

Part of coreos#233.

rust/src/importer.rs

@@ -392,7 +392,7 @@ fn path_is_ostree_compliant(path: &str) -> bool {
         return true;
     }
 
-    if path.starts_with("/usr/") && !path.starts_with("/usr/local") {
+    if path.starts_with("/usr/") {
         return true;
     }
 
@@ -491,7 +491,7 @@ mod tests {
             assert_eq!(path_is_ostree_compliant(entry), false, "{}", entry);
         }
 
-        let denied_cases = &["/var", "/etc", "/var/run", "/usr/local", "", "./", "usr/"];
+        let denied_cases = &["/var", "/etc", "/var/run", "", "./", "usr/"];
         for entry in denied_cases {
             assert_eq!(path_is_ostree_compliant(entry), false, "{}", entry);
         }

tests/vmcheck/test-layering-basic-1.sh

@@ -79,7 +79,8 @@ vm_build_rpm test-usrlocal \
 if vm_rpmostree install test-usrlocal-1.0 2>err.txt; then
     assert_not_reached "Was able to install a package in /usr/local/"
 fi
-assert_file_has_content err.txt "Unsupported path; see https://github.com/projectatomic/rpm-ostree/issues/233"
+# this error is worse now than it used to be now that we experimentally *do* support /usr/local RPMs
+assert_file_has_content err.txt "opendir(local): No such file or directory"
 
 echo "ok failed to install in /usr/local"