Land v8-side changes to switch to v8_current_cpu in the GN build.

test/unittests/BUILD.gn

 # Copyright 2016 The V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # The sources are kept automatically in sync with unittests.gyp.
 
 import("../../gni/v8.gni")
 
 gypi_values = exec_script("//build/gypi_to_gn.py",
                           [ rebase_path("unittests.gyp") ],
                           "scope",
                           [ "unittests.gyp" ])
 
 v8_executable("unittests") {
   testonly = true
 
   sources = gypi_values.unittests_sources
 
-  if (v8_target_cpu == "arm") {
+  if (v8_current_cpu == "arm") {
     sources += gypi_values.unittests_sources_arm
-  } else if (v8_target_cpu == "arm64") {
+  } else if (v8_current_cpu == "arm64") {
     sources += gypi_values.unittests_sources_arm64
-  } else if (v8_target_cpu == "x86") {
+  } else if (v8_current_cpu == "x86") {
     sources += gypi_values.unittests_sources_ia32
-  } else if (v8_target_cpu == "mips" || v8_target_cpu == "mipsel") {
+  } else if (v8_current_cpu == "mips" || v8_current_cpu == "mipsel") {
     sources += gypi_values.unittests_sources_mips
-  } else if (v8_target_cpu == "mips64" || v8_target_cpu == "mips64el") {
+  } else if (v8_current_cpu == "mips64" || v8_current_cpu == "mips64el") {
     sources += gypi_values.unittests_sources_mips64
-  } else if (v8_target_cpu == "x64") {
+  } else if (v8_current_cpu == "x64") {
     sources += gypi_values.unittests_sources_x64
-  } else if (v8_target_cpu == "ppc" || v8_target_cpu == "ppc64") {
+  } else if (v8_current_cpu == "ppc" || v8_current_cpu == "ppc64") {
     sources += gypi_values.unittests_sources_ppc
-  } else if (v8_target_cpu == "s390" || v8_target_cpu == "s390x") {
+  } else if (v8_current_cpu == "s390" || v8_current_cpu == "s390x") {
     sources += gypi_values.unittests_sources_s390
   }
 
   configs = [
     "../..:external_config",
     "../..:internal_config_base",
   ]
 
   # TODO(machenbach): Translate from gyp.
   #['OS=="aix"', {
@@ skipping 24 matching lines @@
 
     # Suppress warnings about importing locally defined symbols.
     if (is_component_build) {
       ldflags = [
         "/ignore:4049",
         "/ignore:4217",
       ]
     }
   }
 }