Fix path component length for zero-length paths canonicalized to '/'.

src/url_canon_unittest.cc

 // Copyright 2007, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 1693 matching lines @@
                                                         &out_parsed);
     output.Complete();
 
     EXPECT_EQ(cases[i].expected_success, success);
     EXPECT_EQ(cases[i].expected, out_str);
 
     // Make sure the spec was properly identified, the filesystem canonicalizer
     // has different code for writing the spec.
     EXPECT_EQ(0, out_parsed.scheme.begin);
     EXPECT_EQ(10, out_parsed.scheme.len);
+    if (success)
+      EXPECT_GT(out_parsed.path.len, 0);
   }
 }
 
 TEST(URLCanonTest, CanonicalizePathURL) {
   // Path URLs should get canonicalized schemes but nothing else.
   struct PathCase {
     const char* input;
     const char* expected;
   } path_cases[] = {
     {"javascript:", "javascript:"},
@@ skipping 395 matching lines @@
   url_canon::StdStringCanonOutput repl_output(&repl_str);
   url_canon::ReplaceFileURL(src, parsed, repl, NULL, &repl_output, &repl_parsed);
   repl_output.Complete();
 
   // Generate the expected string and check.
   std::string expected("file:///foo?");
   for (size_t i = 0; i < new_query.length(); i++)
     expected.push_back('a');
   EXPECT_TRUE(expected == repl_str);
 }