ninja: Add target_rpath generator flag

test/linux/gyptest-target-rpath.py

 #!/usr/bin/env python
 
 # Copyright (c) 2013 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """
-Verifies that the implicit rpath is added only when needed.
+Check target_rpath generator flag for ninja.
 """
 
 import TestGyp
 
 import re
 import subprocess
 import sys
 
 if sys.platform.startswith('linux'):
-  test = TestGyp.TestGyp(formats=['ninja', 'make'])
+  test = TestGyp.TestGyp(formats=['ninja'])
 
-  CHDIR = 'implicit-rpath'
-  test.run_gyp('test.gyp', chdir=CHDIR)
+  CHDIR = 'target-rpath'
+  test.run_gyp('test.gyp', '-G', 'target_rpath=/usr/lib/gyptest/', chdir=CHDIR)
   test.build('test.gyp', test.ALL, chdir=CHDIR)
 
   def GetRpaths(p):
     p = test.built_file_path(p, chdir=CHDIR)
     r = re.compile(r'Library rpath: \[([^\]]+)\]')
     proc = subprocess.Popen(['readelf', '-d', p], stdout=subprocess.PIPE)
     o = proc.communicate()[0]
     assert not proc.returncode
     return r.findall(o)
 
-  if test.format == 'ninja':
-    expect = '$ORIGIN/lib/'
-  elif test.format == 'make':
-    expect = '$ORIGIN/lib.target/'
-  else:
-    test.fail_test()
+  expect = '/usr/lib/gyptest/'
 
   if GetRpaths('shared_executable') != [expect]:
     test.fail_test()
 
   if GetRpaths('shared_executable_no_so_suffix') != [expect]:
     test.fail_test()
 
   if GetRpaths('static_executable'):
     test.fail_test()
 
   test.pass_test()