Don't add BUILD_NUMBER to version for platform builds

We're removing differences between two builds that have the same source.
These builds will have different BUILD_NUMBERs though, so it shouldn't
be embedded in the binary.

For eng builds, using the current date forces the APK to be rebuilt
every time the makefiles are read. Remove this for platform builds, but
keep it if building unbundled.

Bug: 24201956
Change-Id: I8c0ad93e817c74c69b8d8156d4727952b08024d4

version.mk

@@ -100,17 +100,22 @@ endif
 version_code_package := $(base_version_major)$(base_version_minor)$(base_version_build)$(base_version_buildtype)$(base_version_arch)$(base_version_density)
 
 # The version name scheme for the package apk is:
+# - For platform builds:     M.m.bbb
 # - For eng build (t=1):     M.m.bbb eng.$(USER)-hh
 # - For build server (t=0):  M.m.bbb (nnnnnn-hh)
 #       where nnnnnn is the build number from the build server (no zero-padding)
 # On eng builds, the BUILD_NUMBER has the user and timestamp inline
+ifdef TARGET_BUILD_APPS
 ifneq "" "$(filter eng.%,$(BUILD_NUMBER))"
   git_hash := $(shell git --git-dir $(LOCAL_PATH)/.git log -n 1 --pretty=format:%h)
   date_string := $(shell date +%m%d%y_%H%M%S)
   version_name_package := $(base_version_major).$(base_version_minor).$(base_version_build) (eng.$(USER).$(git_hash).$(date_string)-$(base_version_arch)$(base_version_density))
 else
   version_name_package := $(base_version_major).$(base_version_minor).$(base_version_build) ($(BUILD_NUMBER)-$(base_version_arch)$(base_version_density))
 endif
+else # !TARGET_BUILD_APPS
+  version_name_package := $(base_version_major).$(base_version_minor).$(base_version_build)
+endif
 
 # Cleanup the locals
 base_version_major :=