Revert of PPC/s390: [sysroot installer] Disable for host arch PPC/s390

build/linux/sysroot_scripts/install-sysroot.py

Index: build/linux/sysroot_scripts/install-sysroot.py
diff --git a/build/linux/sysroot_scripts/install-sysroot.py b/build/linux/sysroot_scripts/install-sysroot.py
index a746babf16d37699f27b3a61318046088ec74d03..3e842a47cdd9312a1a7af030aa417957684e465f 100755
--- a/build/linux/sysroot_scripts/install-sysroot.py
+++ b/build/linux/sysroot_scripts/install-sysroot.py
@@ -108,10 +108,6 @@
     return 'arm64'
   elif detected_host_arch == 'mips':
     return 'mips'
-  elif detected_host_arch == 'ppc':
-    return 'ppc'
-  elif detected_host_arch == 's390':
-    return 's390'
 
   raise Error('Unrecognized host arch: %s' % detected_host_arch)
 
@@ -182,12 +178,7 @@
   parser.add_option('--arch', type='choice', choices=valid_archs,
                     help='Sysroot architecture: %s' % ', '.join(valid_archs))
   options, _ = parser.parse_args(args)
-  host_arch = DetectHostArch()
   if options.running_as_hook and not sys.platform.startswith('linux'):
-    return 0
-
-  # PPC/s390 don't use sysroot, see http://crbug.com/646169
-  if host_arch in ('ppc','s390'):
     return 0
 
   if options.running_as_hook: