Move detect_v8_host_arch out of gypfiles.

R=machenbach@chromium.org

Bug: v8:7335
Change-Id: I49317fed6c91064109d3adff06b0bba474e11f1d
Reviewed-on: https://chromium-review.googlesource.com/892865
Commit-Queue: Yang Guo <yangguo@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50975}

gypfiles/gyp_v8

@@ -48,7 +48,8 @@ import gyp
 # Add paths so that pymod_do_main(...) can import files.
 sys.path.insert(
     1, os.path.abspath(os.path.join(v8_root, 'tools', 'generate_shim_headers')))
-
+sys.path.append(
+    os.path.abspath(os.path.join(v8_root, 'third_party', 'binutils')))
 
 def GetOutputDirectory():
   """Returns the output directory that GYP will use."""

third_party/binutils/detect_v8_host_arch.py

@@ -38,6 +38,9 @@ def main():
   return 0
 
 def DoMain(_):
+  return DetectHostArch();
+
+def DetectHostArch():
   """Hook to be called from gyp without starting a separate python
   interpreter."""
   host_arch = platform.machine()

third_party/binutils/download.py

@@ -15,6 +15,7 @@ import re
 import shutil
 import subprocess
 import sys
+from detect_v8_host_arch import DetectHostArch
 
 
 BINUTILS_DIR = os.path.abspath(os.path.dirname(__file__))
@@ -22,9 +23,6 @@ BINUTILS_FILE = 'binutils.tar.bz2'
 BINUTILS_TOOLS = ['bin/ld.gold', 'bin/objcopy', 'bin/objdump']
 BINUTILS_OUT = 'Release'
 
-DETECT_HOST_ARCH = os.path.abspath(os.path.join(
-    BINUTILS_DIR, '../../gypfiles/detect_v8_host_arch.py'))
-
 
 def ReadFile(filename):
   with file(filename, 'r') as f:
@@ -48,7 +46,7 @@ def GetArch():
       return 'x64'
     return arch
 
-  return subprocess.check_output(['python', DETECT_HOST_ARCH]).strip()
+  return DetectHostArch()
 
 
 def FetchAndExtract(arch):