Revert of Only run install-debian.wheezy.sysroot.py once during runhooks (patchset #2 id:20001 of https://codereview.chromium.org/834133003/)

Reason for revert:
See failing gclient runhooks after this patch and the Chrome build tree turned red (see http://build.chromium.org/p/chromium.win/waterfall?builder=Win8%20GN for details).

I can't find any other reason for this failure and will will try to revert.

Original issue's description:
> Only run install-debian.wheezy.sysroot.py once during runhooks
>
> This script was previously run three times, once for
> each arch, with two of the three always being no-ops.
>
> Instead just run the script once and have the script
> figure out which image to download.
>
> TEST=trybots + 'gclient runhooks' locally
>
> Committed: https://crrev.com/711802679ce2feb228ad418dd117ae23301e5c02
> Cr-Commit-Position: refs/heads/master@{#310467}

TBR=thestig@chromium.org,sbc@chromium.org
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/843683003

Cr-Commit-Position: refs/heads/master@{#310468}

1 files changed, 45 insertions, 52 deletions

diff --git a/chrome/installer/linux/sysroot_scripts/install-debian.wheezy.sysroot.py b/chrome/installer/linux/sysroot_scripts/install-debian.wheezy.sysroot.py
index 66ee65a..c9248f9 100755
--- a/chrome/installer/linux/sysroot_scripts/install-debian.wheezy.sysroot.py
+++ b/chrome/installer/linux/sysroot_scripts/install-debian.wheezy.sysroot.py
@@ -41,10 +41,8 @@ SYSROOT_DIR_AMD64 = 'debian_wheezy_amd64-sysroot'
 SYSROOT_DIR_I386 = 'debian_wheezy_i386-sysroot'
 SYSROOT_DIR_ARM = 'debian_wheezy_arm-sysroot'
 
-valid_archs = ('arm', 'i386', 'amd64')
 
-
-def GetSha1(filename):
+def get_sha1(filename):
   sha1 = hashlib.sha1()
   with open(filename, 'rb') as f:
     while True:
@@ -56,45 +54,10 @@ def GetSha1(filename):
   return sha1.hexdigest()
 
 
-def DetectArch(gyp_defines):
-  # Check for optional target_arch and only install for that architecture.
-  # If target_arch is not specified, then only install for the host
-  # architecture.
-  if 'target_arch=x64' in gyp_defines:
-    return 'amd64'
-  elif 'target_arch=ia32' in gyp_defines:
-    return 'i386'
-  elif 'target_arch=arm' in gyp_defines:
-    return 'arm'
-  else:
-    # Figure out host arch using build/detect_host_arch.py and
-    # set target_arch to host arch
-    SRC_DIR = os.path.abspath(
-        os.path.join(SCRIPT_DIR, '..', '..', '..', '..'))
-    sys.path.append(os.path.join(SRC_DIR, 'build'))
-    import detect_host_arch
-
-    detected_host_arch = detect_host_arch.HostArch()
-    if detected_host_arch == 'x64':
-      return 'amd64'
-    elif detected_host_arch == 'ia32':
-      return 'i386'
-    elif detected_host_arch == 'arm':
-      return 'arm'
-
-  return None
-
-
 def main():
-  gyp_defines = os.environ.get('GYP_DEFINES', '')
-
-  if options.arch:
-    target_arch = options.arch
-  else:
-    target_arch = DetectArch(gyp_defines)
-    if not target_arch:
-      print 'Unable to detect desired architecture'
-      return 1
+  if options.arch not in ['amd64', 'i386', 'arm']:
+    print 'Unknown architecture: %s' % options.arch
+    return 1
 
   if options.linux_only:
     # This argument is passed when run from the gclient hooks.
@@ -102,9 +65,11 @@ def main():
     if not sys.platform.startswith('linux'):
       return 0
 
+    gyp_defines = os.environ.get('GYP_DEFINES', '')
+
     # Only install the sysroot for an Official Chrome Linux build, except
     # for ARM where we always use a sysroot.
-    if target_arch != 'arm':
+    if options.arch != 'arm':
       defined = ['branding=Chrome', 'buildtype=Official']
       undefined = ['chromeos=1']
       for option in defined:
@@ -114,29 +79,58 @@ def main():
         if option in gyp_defines:
           return 0
 
+    # Check for optional target_arch and only install for that architecture.
+    # If target_arch is not specified, then only install for the host
+    # architecture.
+    target_arch = ''
+    if 'target_arch=x64' in gyp_defines:
+      target_arch = 'amd64'
+    elif 'target_arch=ia32' in gyp_defines:
+      target_arch = 'i386'
+    elif 'target_arch=arm' in gyp_defines:
+      target_arch = 'arm'
+    else:
+      # Figure out host arch using build/detect_host_arch.py and
+      # set target_arch to host arch
+      SRC_DIR = os.path.abspath(
+          os.path.join(SCRIPT_DIR, '..', '..', '..', '..'))
+      sys.path.append(os.path.join(SRC_DIR, 'build'))
+      import detect_host_arch
+
+      detected_host_arch = detect_host_arch.HostArch()
+      if detected_host_arch == 'x64':
+        target_arch = 'amd64'
+      elif detected_host_arch == 'ia32':
+        target_arch = 'i386'
+      elif detected_host_arch == 'arm':
+        target_arch = 'arm'
+
+    if target_arch != options.arch:
+      return 0
+
   # The sysroot directory should match the one specified in build/common.gypi.
   # TODO(thestig) Consider putting this else where to avoid having to recreate
   # it on every build.
   linux_dir = os.path.dirname(SCRIPT_DIR)
-  if target_arch == 'amd64':
+  if options.arch == 'amd64':
     sysroot = os.path.join(linux_dir, SYSROOT_DIR_AMD64)
     tarball_filename = TARBALL_AMD64
     tarball_sha1sum = TARBALL_AMD64_SHA1SUM
     revision = REVISION_AMD64
-  elif target_arch == 'arm':
+  elif options.arch == 'arm':
     sysroot = os.path.join(linux_dir, SYSROOT_DIR_ARM)
     tarball_filename = TARBALL_ARM
     tarball_sha1sum = TARBALL_ARM_SHA1SUM
     revision = REVISION_ARM
-  elif target_arch == 'i386':
+  elif options.arch == 'i386':
     sysroot = os.path.join(linux_dir, SYSROOT_DIR_I386)
     tarball_filename = TARBALL_I386
     tarball_sha1sum = TARBALL_I386_SHA1SUM
     revision = REVISION_I386
   else:
-    print 'Unknown architecture: %s' % target_arch
     assert(False)
 
+
   url = '%s/%s/%s/%s' % (URL_PREFIX, URL_PATH, revision, tarball_filename)
 
   stamp = os.path.join(sysroot, '.stamp')
@@ -144,10 +138,10 @@ def main():
     with open(stamp) as s:
       if s.read() == url:
         print 'Debian Wheezy %s root image already up-to-date: %s' % \
-            (target_arch, sysroot)
+            (options.arch, sysroot)
         return 0
 
-  print 'Installing Debian Wheezy %s root image: %s' % (target_arch, sysroot)
+  print 'Installing Debian Wheezy %s root image: %s' % (options.arch, sysroot)
   if os.path.isdir(sysroot):
     shutil.rmtree(sysroot)
   os.mkdir(sysroot)
@@ -156,7 +150,7 @@ def main():
   sys.stdout.flush()
   sys.stderr.flush()
   subprocess.check_call(['curl', '--fail', '-L', url, '-o', tarball])
-  sha1sum = GetSha1(tarball)
+  sha1sum = get_sha1(tarball)
   if sha1sum != tarball_sha1sum:
     print 'Tarball sha1sum is wrong.'
     print 'Expected %s, actual: %s' % (tarball_sha1sum, sha1sum)
@@ -174,7 +168,6 @@ if __name__ == '__main__':
   parser.add_option('--linux-only', action='store_true',
                     default=False, help='Only install sysroot for official '
                                         'Linux builds')
-  parser.add_option('--arch', type='choice', choices=valid_archs,
-                    help='Sysroot architecture: %s' % ', '.join(valid_archs))
-  options, _ = parser.parse_args()
+  parser.add_option('--arch', help='Sysroot architecture: i386, amd64 or arm')
+  options, args = parser.parse_args()
   sys.exit(main())