Support relative file paths in FilePathToFileURL().

This makes it possible for content_shell to resolve relative file paths
on the command line and turn them into proper startup URLs.

BUG=336416

Review URL: https://codereview.chromium.org/137233006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246278 0039d316-1c4b-4281-b951-d872f2087c98

net/base/net_util.cc

@@ -998,6 +998,12 @@ GURL FilePathToFileURL(const base::FilePath& path) {
   // "file://///server/path" for UNC. The URL canonicalizer will fix up the
   // latter case to be the canonical UNC form: "file://server/path"
   base::FilePath::StringType url_string(kFileURLPrefix);
+  if (!path.IsAbsolute()) {
+    base::FilePath current_dir;
+    PathService::Get(base::DIR_CURRENT, &current_dir);
+    url_string.append(current_dir.value());
+    url_string.push_back(base::FilePath::kSeparators[0]);
+  }
   url_string.append(path.value());
 
   // Now do replacement of some characters. Since we assume the input is a