remoting: fix out-of-tree build

remoting/webapp/build_template.gni

Index: remoting/webapp/build_template.gni
diff --git a/remoting/webapp/build_template.gni b/remoting/webapp/build_template.gni
index 3fcf0aa7b9cc7cec386fd7078b82b4f22ea3ede1..725637b960f0432ac6dcc856fd8193a5f158ec58 100644
--- a/remoting/webapp/build_template.gni
+++ b/remoting/webapp/build_template.gni
@@ -95,7 +95,7 @@ template("build_webapp_html") {
     exclude_js = invoker.exclude_js
     instrument_js = invoker.instrument_js
 
-    script = rebase_path("//remoting/webapp/build-html.py", root_build_dir)
+    script = rebase_path("//remoting/webapp/build-html.py")
 
     # Create a file that contains a list of all the JavaScript files needed
     # to build the unit test page. This is needed to avoid problems on platforms
@@ -237,9 +237,8 @@ template("desktop_remoting_webapp") {
       }
     }
 
-    inputs = [ rebase_path("crd/manifest.json.jinja2", root_build_dir) ] +
-             remoting_version_files +
-             rebase_path(remoting_webapp_crd_files, root_build_dir) +
+    inputs = [ rebase_path("crd/manifest.json.jinja2") ] +
+             remoting_version_files + rebase_path(remoting_webapp_crd_files) +
              extra_files + dr_generated_html_files
 
     outputs = [