Change cxxflags test to build in same env as gyp (+ test make instead of ninja)

test/cxxflags/gyptest-cxxflags.py

Index: test/cxxflags/gyptest-cxxflags.py
diff --git a/test/cxxflags/gyptest-cxxflags.py b/test/cxxflags/gyptest-cxxflags.py
index b8bed7f9c2c5a6c102e1ea2a70adf46f08ef309a..bf7841b582fce292eb873dac9999e73e6f33bf62 100755
--- a/test/cxxflags/gyptest-cxxflags.py
+++ b/test/cxxflags/gyptest-cxxflags.py
@@ -9,21 +9,21 @@ Verifies the use of the environment during regeneration when the gyp file
 changes, specifically via build of an executable with C++ flags specified by
 CXXFLAGS.
 
-In this test, gyp happens within a local environment, but build outside of it.
+In this test, gyp and build both run in same local environment.
+(Build with different environment has different results for some build
+systems and platforms.)
 """
 
 import TestGyp
 
-FORMATS = ('ninja',)
+# ninja fails on Windows; contrast with cflags test
+FORMATS = ('make',)
 
 test = TestGyp.TestGyp(formats=FORMATS)
 
-# We reset the environ after calling gyp. When the auto-regeneration happens,
-# the same define should be reused anyway.
 with TestGyp.LocalEnv({'CXXFLAGS': '-O0'}):
   test.run_gyp('cxxflags.gyp')
-
-test.build('cxxflags.gyp')
+  test.build('cxxflags.gyp')
 
 expect = """\
 Using no optimization flag
@@ -34,8 +34,7 @@ test.sleep()
 
 with TestGyp.LocalEnv({'CXXFLAGS': '-O2'}):
   test.run_gyp('cxxflags.gyp')
-
-test.build('cxxflags.gyp')
+  test.build('cxxflags.gyp')
 
 expect = """\
 Using an optimization flag