Updates version number to 0.4.178909500.20171213.

Significant changes:
- Fixed ENV var issue with Swift tests.
- Skylark sources (.bzl, BUILD) will not be added to the
  generated project by default anymore.
- Project generation performance improvements.
- Improved Objc module support in Swift.

--
PiperOrigin-RevId: 178918504
MOS_MIGRATED_REVID=178918504
diff --git a/src/XcodeConfig/TulsiVersion.xcconfig b/src/XcodeConfig/TulsiVersion.xcconfig
index 1d8af02..7f6719b 100644
--- a/src/XcodeConfig/TulsiVersion.xcconfig
+++ b/src/XcodeConfig/TulsiVersion.xcconfig
@@ -8,8 +8,8 @@
 // Version number (recorded into the Info.plist)
 TULSI_VERSION_MAJOR = 0
 TULSI_VERSION_MINOR = $(GOOGLE_VERSION_BUILDNUMBER)
-TULSI_VERSION_FIXLEVEL = 178277830
-TULSI_VERSION_BUILDNUMBER = 20171207
+TULSI_VERSION_FIXLEVEL = 178909500
+TULSI_VERSION_BUILDNUMBER = 20171213
 
 TULSI_VERSION_COPYRIGHT = 2015-2017