Restat shared library link ops in GN on Windows.

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.
 
 declare_args() {
   # Path to the directory containing the VC binaries for the right
   # combination of host and target architectures. Currently only the
   # 64-bit host toolchain is supported, with either 32-bit or 64-bit targets.
   # If vc_bin_dir is not specified on the command line (and it normally
   # isn't), we will dynamically determine the right value to use at runtime.
@@ skipping 145 matching lines @@
 
       default_output_extension = ".dll"
       description = "LINK(DLL) {{output}}"
       outputs = [
         dllname,
         libname,
       ]
       link_output = libname
       depend_output = libname
 
+      # 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}}"
     }
 
     tool("link") {
       rspfile = "{{output}}.rsp"
 
       link_command = "$python_path gyp-win-tool link-wrapper $env False link.exe /nologo /OUT:{{output}} /PDB:{{output}}.pdb @$rspfile"
 
@@ skipping 87 matching lines @@
 }
 
 msvc_toolchain("winrt_x64") {
   environment = "environment.winrt_x64"
   cl = "${goma_prefix}\"${vc_bin_dir}/cl.exe\""
   is_clang = false
 
   current_cpu = "x64"
   current_os = current_os
 }