Add TestGypXcodeNinja to run tests against the xcode-ninja generator

test/copies/gyptest-samedir.py

Index: test/copies/gyptest-samedir.py
diff --git a/test/copies/gyptest-samedir.py b/test/copies/gyptest-samedir.py
index 3f0c547300e2c4dbebc6b8b0819dfb6f87918f15..a271b38f077092fae5e69e12543a4b7d86678789 100755
--- a/test/copies/gyptest-samedir.py
+++ b/test/copies/gyptest-samedir.py
@@ -13,7 +13,10 @@ import TestGyp
 
 # The Android build system doesn't allow output to go to arbitrary places.
 test = TestGyp.TestGyp(formats=['!android'])
-test.run_gyp('copies-samedir.gyp', chdir='src')
+test.run_gyp('copies-samedir.gyp',
+             '-G', 'xcode_ninja_target_pattern=^copies_samedir',
+             chdir='src')
+
 test.relocate('src', 'relocate/src')
 test.build('copies-samedir.gyp', 'copies_samedir', chdir='relocate/src')