Add Platform.CodeName to source.properties

This does not use the placeholder because it doesn't seem
to work when the platform loses its codename.

Change-Id: I98a828915fe23f2fb777e329289303f17b05a60e
diff --git a/sdk/platform_source.prop_template b/sdk/platform_source.prop_template
index bb7a6b8..c6756e8 100644
--- a/sdk/platform_source.prop_template
+++ b/sdk/platform_source.prop_template
@@ -1,6 +1,7 @@
 Pkg.Desc=Android SDK Platform ${PLATFORM_VERSION}
 Pkg.UserSrc=false
 Platform.Version=${PLATFORM_VERSION}
+Platform.CodeName=Jelly Bean
 Pkg.Revision=1
 AndroidVersion.ApiLevel=${PLATFORM_SDK_VERSION}
 AndroidVersion.CodeName=${PLATFORM_VERSION_CODENAME}