Fix rebase path misuses.

mojo/nacl/nonsfi/BUILD.gn

 # 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.
 
 # Trusted code
 if (!is_nacl) {
   # A simple shell for running untrusted binaries that talk to the Mojo
   # embedder. (No services.)
   if (current_cpu == "x86" || current_cpu == "arm") {
     # Non-SFI NaCl currently supports x86-32 and ARMv7, but not anything 64-bit.
@@ skipping 67 matching lines @@
 
 action("translate_mojo_pnacl_tests_to_native") {
   testonly = true
 
   # Leaving default as linux for OSes which are similar to linux, but do
   # not self-identify as linux through host_os.
   nacl_toolchain_host_os = "linux"
   if (host_os == "mac") {
     nacl_toolchain_host_os = "mac"
   }
-  script = rebase_path("//") + "native_client/toolchain/${nacl_toolchain_host_os}_x86/pnacl_newlib/bin/pydir/loader.py"
-  input = rebase_path(root_build_dir) + "/newlib_pnacl/monacl_test.pexe"
+  script = rebase_path(
+          "//native_client/toolchain/${nacl_toolchain_host_os}_x86/pnacl_newlib/bin/pydir/loader.py")
+  input = rebase_path("${root_build_dir}/newlib_pnacl/monacl_test.pexe")
   inputs = [
     input,
   ]
   output = "monacl_test_nonsfi.nexe"
   outputs = [
     "$root_out_dir/${output}",
   ]
   args = [
     "pnacl-translate",
     "$input",
     "-o",
     "$output",
     "-arch",
   ]
   if (target_cpu == "x86" || target_cpu == "x64") {
     args += [ "x86-32-nonsfi" ]
   } else if (target_cpu == "arm") {
     args += [ "arm-nonsfi" ]
   } else {
     assert(false, "Unrecognized target CPU for Non-SFI NaCl translation")
   }
   deps = [
     ":mojo_pnacl_tests",
   ]
 }
 
 action("prepend_shebang_to_nexe") {
   testonly = true
 
-  script = rebase_path("//") + "mojo/public/tools/prepend.py"
+  script = rebase_path("//mojo/public/tools/prepend.py")
   nexe_path = "$root_out_dir/monacl_test_nonsfi"
   input = "${nexe_path}.nexe"
   inputs = [
     input,
   ]
   output = "${nexe_path}.mojo"
   outputs = [
     output,
   ]
 
@@ skipping 16 matching lines @@
   ]
 }
 
 group("mojo_nacl_tests_nonsfi") {
   testonly = true
   deps = [
     ":monacl_shell_nonsfi_x86",
     ":monacl_test_nonsfi_nexes",
   ]
 }