Fix the WinAsan dependency to thunk dll.

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/compiler/compiler.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")
@@ skipping 267 matching lines @@
 
       # These share a name with global variables that are already defined, and
       # forward_variables_from won't clobber the existing value, so we need to
       # set it explicitly.
       if (defined(invoker.is_clang)) {
         is_clang = invoker.is_clang
       }
       if (defined(invoker.is_component_build)) {
         is_component_build = invoker.is_component_build
       }
+      if (defined(invoker.is_asan)) {
+        is_asan = invoker.is_asan
+      }
 
       # This value needs to be passed through unchanged.
       host_toolchain = host_toolchain
     }
   }
 }
 
 if (is_clang) {
   sys_include_prefix = "-imsvc"
 } else {
@@ skipping 64 matching lines @@
     environment = "environment.x64"
     toolchain_cpu = "x64"
     cl = "${goma_prefix}\"${x64_toolchain_data.vc_bin_dir}/cl.exe\""
     is_clang = false
 
     # This shares a name with a global and forward_variables_from won't clobber
     # the existing value, so we need to set it explicitly.
     if (defined(invoker.is_component_build)) {
       is_component_build = invoker.is_component_build
     }
+    if (defined(invoker.is_asan)) {
+      is_asan = invoker.is_asan
+    }
   }
 
   msvc_toolchain("clang_" + target_name) {
     environment = "environment.x64"
     toolchain_cpu = "x64"
     prefix = rebase_path("$clang_base_path/bin", root_build_dir)
     cl = "${goma_prefix}$prefix/${clang_cl}"
     toolchain_os = "win"
     is_clang = true
     sys_include_flags = "${x64_toolchain_data.include_flags}"
 
     # This shares a name with a global and forward_variables_from won't clobber
     # the existing value, so we need to set it explicitly.
     if (defined(invoker.is_component_build)) {
       is_component_build = invoker.is_component_build
     }
+    if (defined(invoker.is_asan)) {
+      is_asan = invoker.is_asan
+    }
   }
 }
 
 win_x64_toolchains("x64") {
   # TODO(mcgrathr): These assignments are only required because of
   # crbug.com/395883.  Drop them if that ever gets fixed in GN.
   concurrent_links = concurrent_links
   goma_prefix = goma_prefix
   x64_toolchain_data = x64_toolchain_data
+  if (target_cpu == "x86") {
+    is_asan = false
+  }
 }
 
 # The nacl_win64 toolchain is nearly identical to the plain x64 toolchain.
 # It's used solely for building nacl64.exe (//components/nacl/broker:nacl64).
 # The only reason it's a separate toolchain is so that it can force
 # is_component_build to false in the toolchain_args() block, because
 # building nacl64.exe in component style does not work.
 win_x64_toolchains("nacl_win64") {
   is_component_build = false
+  is_asan = false
 
   # TODO(mcgrathr): These assignments are only required because of
   # crbug.com/395883.  Drop them if that ever gets fixed in GN.
   concurrent_links = concurrent_links
   goma_prefix = goma_prefix
   x64_toolchain_data = x64_toolchain_data
   clang_cl = clang_cl
 }
 
 # WinRT toolchains. Only define these when targeting them.
@@ skipping 14 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
   }
 }