chromeos/printing: Small fix in URL parsing

This patch modifies CHECK condition in a function responsible for
extracting hostname and port from given URI. The previous CHECK
version was activated for some boundary cases like "://".

BUG=none
TEST=on my workstation with the fuzzer from CL:2079133

Change-Id: Ie5604128b1f5ae4e0ab97117421dd1f79f2f8b38
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2080713
Commit-Queue: Sean Kau <skau@chromium.org>
Reviewed-by: Sean Kau <skau@chromium.org>
Auto-Submit: Piotr Pawliczek <pawliczek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745653}

chromeos/printing/printer_configuration.cc

@@ -99,7 +99,7 @@ base::StringPiece HostAndPort(base::StringPiece uri) {
     hostname_end = uri.size();
   }
 
-  CHECK_GT(hostname_end, hostname_start);
+  CHECK_GE(hostname_end, hostname_start);
   return uri.substr(hostname_start, hostname_end - hostname_start);
 }