Revert r1978 and r1979

BUG=

Review URL: https://codereview.chromium.org/594923002

git-svn-id: http://gyp.googlecode.com/svn/trunk@1982 78cadc50-ecff-11dd-a971-7dbc132099af
diff --git a/pylib/gyp/MSVSVersion.py b/pylib/gyp/MSVSVersion.py
index 8b01f7a..bcd6122 100644
--- a/pylib/gyp/MSVSVersion.py
+++ b/pylib/gyp/MSVSVersion.py
@@ -401,5 +401,9 @@
   version = str(version)
   versions = _DetectVisualStudioVersions(version_map[version], 'e' in version)
   if not versions:
-    raise ValueError('Could not locate Visual Studio installation.')
+    if version == 'auto':
+      # Default to 2005 if we couldn't find anything
+      return _CreateVersion('2005', None)
+    else:
+      return _CreateVersion(version, None)
   return versions[0]
diff --git a/pylib/gyp/generator/ninja_test.py b/pylib/gyp/generator/ninja_test.py
index 1767b2f..52661bc 100644
--- a/pylib/gyp/generator/ninja_test.py
+++ b/pylib/gyp/generator/ninja_test.py
@@ -15,18 +15,15 @@
 
 class TestPrefixesAndSuffixes(unittest.TestCase):
   def test_BinaryNamesWindows(self):
-    # These cannot run on non-Windows as they require a VS installation to
-    # correctly handle variable expansion.
-    if sys.platform.startswith('win'):
-      writer = ninja.NinjaWriter('foo', 'wee', '.', '.', 'build.ninja', '.',
-          'build.ninja', 'win')
-      spec = { 'target_name': 'wee' }
-      self.assertTrue(writer.ComputeOutputFileName(spec, 'executable').
-          endswith('.exe'))
-      self.assertTrue(writer.ComputeOutputFileName(spec, 'shared_library').
-          endswith('.dll'))
-      self.assertTrue(writer.ComputeOutputFileName(spec, 'static_library').
-          endswith('.lib'))
+    writer = ninja.NinjaWriter('foo', 'wee', '.', '.', 'build.ninja', '.',
+        'build.ninja', 'win')
+    spec = { 'target_name': 'wee' }
+    self.assertTrue(writer.ComputeOutputFileName(spec, 'executable').
+        endswith('.exe'))
+    self.assertTrue(writer.ComputeOutputFileName(spec, 'shared_library').
+        endswith('.dll'))
+    self.assertTrue(writer.ComputeOutputFileName(spec, 'static_library').
+        endswith('.lib'))
 
   def test_BinaryNamesLinux(self):
     writer = ninja.NinjaWriter('foo', 'wee', '.', '.', 'build.ninja', '.',