Revert of [NaCl SDK] Remove create_nmf dependency on NACL_SDK_ROOT env var (patchset #5 id:80001 of https://codereview.chromium.org/737653003/)

Reason for revert:
Broke compile on Google Chrome ChromeOS bot.

[8069/19495] CXX obj/components/policy/core/common/cloud/policy_component_common.external_policy_data_updater.o
FAILED: cd ../../third_party/liblouis; python ../../native_client_sdk/src/tools/create_nmf.py ../../out/Release/chromevox_test_data/braille/liblouis_nacl_x86_64.nexe "--output=../../out/Release/chromevox_test_data/braille/liblouis_nacl.nmf"
Traceback (most recent call last):
  File "../../native_client_sdk/src/tools/create_nmf.py", line 680, in <module>
    rtn = main(sys.argv[1:])
  File "../../native_client_sdk/src/tools/create_nmf.py", line 633, in main
    options.lib_path += GetDefaultLibPath(config)
  File "../../native_client_sdk/src/tools/create_nmf.py", line 507, in GetDefaultLibPath
    sdk_root = GetSDKRoot()
  File "../../native_client_sdk/src/tools/create_nmf.py", line 478, in GetSDKRoot
    assert(os.path.exists(os.path.join(sdk_root, 'toolchain')))
AssertionError
ninja: build stopped: subcommand failed.

http://build.chromium.org/p/chromium.chrome/builders/Google%20Chrome%20ChromeOS/builds/76569

Original issue's description:
> [NaCl SDK] Remove create_nmf dependency on NACL_SDK_ROOT env var
>
> create_nmf should determine the root of the SDK relative
> to its own location.
>
> The exception to this is when its run as part of the
> chrome build, when it is not yet installed.  In this
> case we pass --no-default-libpath and --objdump to
> create_nmf to remove any use of the SDK root.
>
> Committed: https://crrev.com/088561ac99314a79866a39f79bb32bd5e1196217
> Cr-Commit-Position: refs/heads/master@{#313957}

TBR=binji@chromium.org,dmichael@chromium.org,sbc@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/890033003

Cr-Commit-Position: refs/heads/master@{#313963}

4 files changed, 39 insertions, 39 deletions

diff --git a/native_client_sdk/src/tools/create_nmf.py b/native_client_sdk/src/tools/create_nmf.py
index dc7e552..de72408 100755
--- a/native_client_sdk/src/tools/create_nmf.py
+++ b/native_client_sdk/src/tools/create_nmf.py
@@ -466,16 +466,15 @@ def ParseExtraFiles(encoded_list, err):
 
 
 def GetSDKRoot():
-  """Returns the root directory of the NaCl SDK.
+  """Determine current NACL_SDK_ROOT, either via the environment variable
+  itself, or by attempting to derive it from the location of this script.
   """
-  # This script should be installed in NACL_SDK_ROOT/tools. Assert that
-  # the 'toolchain' folder exists within this directory in case, for
-  # example, this script is moved to a different location.
-  # During the Chrome build this script is sometimes run outside of
-  # of an SDK but in these cases it should always be run with --objdump=
-  # and --no-default-libpath which avoids the need to call this function.
-  sdk_root = os.path.dirname(SCRIPT_DIR)
-  assert(os.path.exists(os.path.join(sdk_root, 'toolchain')))
+  sdk_root = os.environ.get('NACL_SDK_ROOT')
+  if not sdk_root:
+    sdk_root = os.path.dirname(SCRIPT_DIR)
+    if not os.path.exists(os.path.join(sdk_root, 'toolchain')):
+      return None
+
   return sdk_root
 
 
@@ -483,8 +482,12 @@ def FindObjdumpExecutable():
   """Derive path to objdump executable to use for determining shared
   object dependencies.
   """
+  sdk_root = GetSDKRoot()
+  if not sdk_root:
+    return None
+
   osname = getos.GetPlatform()
-  toolchain = os.path.join(GetSDKRoot(), 'toolchain', '%s_x86_glibc' % osname)
+  toolchain = os.path.join(sdk_root, 'toolchain', '%s_x86_glibc' % osname)
   objdump = os.path.join(toolchain, 'bin', 'x86_64-nacl-objdump')
   if osname == 'win':
     objdump += '.exe'
@@ -505,6 +508,10 @@ def GetDefaultLibPath(config):
   """
   assert(config in ('Debug', 'Release'))
   sdk_root = GetSDKRoot()
+  if not sdk_root:
+    # TOOD(sbc): output a warning here?  We would also need to suppress
+    # the warning when run from the chromium build.
+    return []
 
   osname = getos.GetPlatform()
   libpath = [
@@ -573,8 +580,8 @@ def main(args):
                       help='Rename FOO as BAR',
                       action='append', default=[], metavar='FOO,BAR')
   parser.add_argument('-x', '--extra-files',
-                      help='Add extra key:file tuple to the "files"'
-                           ' section of the .nmf',
+                      help=('Add extra key:file tuple to the "files"' +
+                            ' section of the .nmf'),
                       action='append', default=[], metavar='FILE')
   parser.add_argument('-O', '--pnacl-optlevel',
                       help='Set the optimization level to N in PNaCl manifests',
@@ -662,7 +669,7 @@ def main(args):
                  pnacl_debug_optlevel=pnacl_debug_optlevel,
                  nmf_root=nmf_root)
 
-  if options.output is None:
+  if not options.output:
     sys.stdout.write(nmf.GetJson())
   else:
     with open(options.output, 'w') as output:
diff --git a/native_client_sdk/src/tools/tests/create_nmf_test.py b/native_client_sdk/src/tools/tests/create_nmf_test.py
index d71bee9..86a89a2 100755
--- a/native_client_sdk/src/tools/tests/create_nmf_test.py
+++ b/native_client_sdk/src/tools/tests/create_nmf_test.py
@@ -14,19 +14,17 @@ import unittest
 SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
 TOOLS_DIR = os.path.dirname(SCRIPT_DIR)
 DATA_DIR = os.path.join(TOOLS_DIR, 'lib', 'tests', 'data')
-BUILD_TOOLS_DIR = os.path.join(os.path.dirname(TOOLS_DIR), 'build_tools')
 CHROME_SRC = os.path.dirname(os.path.dirname(os.path.dirname(TOOLS_DIR)))
 MOCK_DIR = os.path.join(CHROME_SRC, 'third_party', 'pymock')
 
 # For the mock library
 sys.path.append(MOCK_DIR)
 sys.path.append(TOOLS_DIR)
-sys.path.append(BUILD_TOOLS_DIR)
 
 import build_paths
 import create_nmf
 import getos
-from mock import patch, Mock
+import mock
 
 TOOLCHAIN_OUT = os.path.join(build_paths.OUT_DIR, 'sdk_tests', 'toolchain')
 NACL_X86_GLIBC_TOOLCHAIN = os.path.join(TOOLCHAIN_OUT,
@@ -63,18 +61,24 @@ class TestPosixRelPath(unittest.TestCase):
 
 
 class TestDefaultLibpath(unittest.TestCase):
-  def setUp(self):
-    patcher = patch('create_nmf.GetSDKRoot', Mock(return_value='/dummy/path'))
-    patcher.start()
-    self.addCleanup(patcher.stop)
-
-  def testUsesSDKRoot(self):
-    paths = create_nmf.GetDefaultLibPath('Debug')
+  def testWithoutNaClSDKRoot(self):
+    """GetDefaultLibPath wihtout NACL_SDK_ROOT set
+
+    In the absence of NACL_SDK_ROOT GetDefaultLibPath should
+    return the empty list."""
+    with mock.patch.dict('os.environ', clear=True):
+      paths = create_nmf.GetDefaultLibPath('Debug')
+    self.assertEqual(paths, [])
+
+  def testHonorNaClSDKRoot(self):
+    with mock.patch.dict('os.environ', {'NACL_SDK_ROOT': '/dummy/path'}):
+      paths = create_nmf.GetDefaultLibPath('Debug')
     for path in paths:
       self.assertTrue(path.startswith('/dummy/path'))
 
   def testIncludesNaClPorts(self):
-    paths = create_nmf.GetDefaultLibPath('Debug')
+    with mock.patch.dict('os.environ', {'NACL_SDK_ROOT': '/dummy/path'}):
+      paths = create_nmf.GetDefaultLibPath('Debug')
     self.assertTrue(any(os.path.join('ports', 'lib') in p for p in paths),
                     "naclports libpath missing: %s" % str(paths))
 
diff --git a/ppapi/ppapi_nacl.gyp b/ppapi/ppapi_nacl.gyp
index aab96ef..bbad955 100644
--- a/ppapi/ppapi_nacl.gyp
+++ b/ppapi/ppapi_nacl.gyp
@@ -139,10 +139,6 @@
           '--strip-all',
         ],
         'create_nmf': '<(DEPTH)/native_client_sdk/src/tools/create_nmf.py',
-        'create_nmf_flags': [
-          '--no-default-libpath',
-          '--objdump=>(nacl_glibc_tc_root)/bin/x86_64-nacl-objdump',
-        ],
         'create_nonsfi_test_nmf': 'tests/create_nonsfi_test_nmf.py',
       },
       'conditions': [
@@ -153,6 +149,7 @@
             # doesn't work on Windows.
             'libdir_glibc64': '>(nacl_glibc_tc_root)/x86_64-nacl/lib',
             'libdir_glibc32': '>(nacl_glibc_tc_root)/x86_64-nacl/lib32',
+            'nacl_objdump': '>(nacl_glibc_tc_root)/bin/x86_64-nacl-objdump',
             'nmf_glibc%': '<(PRODUCT_DIR)/>(nexe_target)_glibc.nmf',
           },
           'actions': [
@@ -168,7 +165,7 @@
             'action': [
               'python',
               '>@(_inputs)',
-              '>@(create_nmf_flags)',
+              '--objdump=>(nacl_objdump)',
               '--output=>(nmf_glibc)',
               '--stage-dependencies=<(PRODUCT_DIR)',
             ],
@@ -221,7 +218,6 @@
               'action': [
                 'python',
                 '>@(_inputs)',
-                '>@(create_nmf_flags)',
                 '--output=>(nmf_pnacl)',
               ],
               'conditions': [
@@ -310,7 +306,6 @@
               'action': [
                 'python',
                 '>@(_inputs)',
-                '>@(create_nmf_flags)',
                 '--output=>(nmf_pnacl)',
               ],
             },
@@ -334,7 +329,6 @@
               'action': [
                 'python',
                 '>@(_inputs)',
-                '>@(create_nmf_flags)',
                 '--output=>(nmf_pnacl)',
               ],
             },
diff --git a/ppapi/ppapi_nacl_test_common.gypi b/ppapi/ppapi_nacl_test_common.gypi
index c5e8a6f..ea61327 100644
--- a/ppapi/ppapi_nacl_test_common.gypi
+++ b/ppapi/ppapi_nacl_test_common.gypi
@@ -110,10 +110,6 @@
           'create_nmf': '<(DEPTH)/native_client_sdk/src/tools/create_nmf.py',
           'create_nmf_args_portable%': [],
           'create_nonsfi_test_nmf': '<(DEPTH)/ppapi/tests/create_nonsfi_test_nmf.py',
-          'create_nmf_args': [
-            '--no-default-libpath',
-            '--objdump=>(nacl_glibc_tc_root)/bin/x86_64-nacl-objdump',
-          ],
         },
         'target_conditions': [
           ['generate_nmf==1 and build_newlib==1', {
@@ -125,7 +121,6 @@
                 'action': [
                   'python',
                   '>(create_nmf)',
-                  '>@(create_nmf_args)',
                   '--output=>(nmf_newlib)',
                   '>@(create_nmf_args_portable)',
                 ],
@@ -156,6 +151,7 @@
               # doesn't work on Windows.
               'libdir_glibc64': '>(nacl_glibc_tc_root)/x86_64-nacl/lib',
               'libdir_glibc32': '>(nacl_glibc_tc_root)/x86_64-nacl/lib32',
+              'nacl_objdump': '>(nacl_glibc_tc_root)/bin/x86_64-nacl-objdump',
             },
             'actions': [
               {
@@ -168,7 +164,7 @@
                 'action': [
                   'python',
                   '>@(_inputs)',
-                  '>@(create_nmf_args)',
+                  '--objdump=>(nacl_objdump)',
                   '--output=>(nmf_glibc)',
                   '--path-prefix=>(nexe_target)_libs',
                   '--stage-dependencies=<(nacl_glibc_out_dir)',
@@ -205,7 +201,6 @@
                 'action': [
                   'python',
                   '>(create_nmf)',
-                  '>@(create_nmf_args)',
                   '--output=>(nmf_pnacl_newlib)',
                   '>(out_pnacl_newlib)',
                   '>@(create_nmf_args_portable)',