Reduce absolute paths in generated ninja files

remoting/tools/build/remoting_localize.gni

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Calls the remoting_localize script with a jinja2 template.
 #
 # Arguments
 #
 #   sources (required)
 #     List of jinja2 files to load. This is the template.
@@ skipping 58 matching lines @@
           i,
         ]
       }
     }
 
     # Add variables to command line.
     if (defined(invoker.variables)) {
       foreach(i, invoker.variables) {
         args += [
           "--variables",
-          i,
+          rebase_path(i, root_build_dir),
         ]
       }
     }
 
     # The template file is required.
     args += [
       "--template",
       "{{source}}",
     ]
 
@@ skipping 14 matching lines @@
     if (defined(invoker.deps)) {
       deps = invoker.deps
     } else {
       deps = []
     }
 
     # This script reads the messages strings from the generated resource files.
     deps += [ "//remoting/resources:strings" ]
   }
 }