Allow GN toolchains to specify runtime deps outputs.

build/toolchain/win/BUILD.gn

 # Copyright (c) 2013 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.
 
 import("//build/config/clang/clang.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/win/visual_studio_version.gni")
 import("//build/toolchain/goma.gni")
 import("//build/toolchain/toolchain.gni")
 import("//build/toolchain/concurrent_links.gni")
@@ skipping 174 matching lines @@
 
       default_output_extension = ".dll"
       default_output_dir = "{{root_out_dir}}"
       description = "LINK(DLL) {{output}}"
       outputs = [
         dllname,
         libname,
       ]
       link_output = libname
       depend_output = libname
+
+      # The new version of GN uses a runtime_outputs list rather than a
+      # runtime_link_output string. This needs to be flipped for the next GN
+      # roll.
+      # TODO(brettw) bug 631242: Swap this and remove the old one.
+      #runtime_outputs = [ dllname ]
       runtime_link_output = dllname
 
       # Since the above commands only updates the .lib file when it changes, ask
       # Ninja to check if the timestamp actually changed to know if downstream
       # dependencies should be recompiled.
       restat = true
 
       # The use of inputs_newline is to work around a fixed per-line buffer
       # size in the linker.
       rspfile_content = "{{libs}} {{solibs}} {{inputs_newline}} {{ldflags}}"
@@ skipping 208 matching lines @@
 
   msvc_toolchain("winrt_x64") {
     environment = "environment.winrt_x64"
     cl = "${goma_prefix}\"${vc_bin_dir}/cl.exe\""
     is_clang = false
 
     toolchain_cpu = "x64"
     toolchain_os = current_os
   }
 }