service_contexts: strip blank lines and comments

Strip whitespace and comments from service_context files
to reduce size. On an aosp_x86_64 build it saves 36 bytes.

However, on builds with more synclines and comments, further
space savings can be realized.

Change-Id: I3cb4effad1d1b404bf53605a3793e3070cb95651
Signed-off-by: William Roberts <william.c.roberts@intel.com>

Android.mk

@@ -413,8 +413,8 @@ $(service_contexts.tmp): $(all_svcfiles_with_nl)
 $(LOCAL_BUILT_MODULE): PRIVATE_SEPOLICY := $(built_sepolicy)
 $(LOCAL_BUILT_MODULE): $(service_contexts.tmp) $(built_sepolicy) $(HOST_OUT_EXECUTABLES)/checkfc $(ACP)
 	@mkdir -p $(dir $@)
-	$(hide) $(HOST_OUT_EXECUTABLES)/checkfc -s $(PRIVATE_SEPOLICY) $<
-	$(hide) $(ACP) $< $@
+	sed -e 's/#.*$$//' -e '/^$$/d' $< > $@
+	$(hide) $(HOST_OUT_EXECUTABLES)/checkfc -s $(PRIVATE_SEPOLICY) $@
 
 built_svc := $(LOCAL_BUILT_MODULE)
 all_svc_files :=
@@ -438,8 +438,8 @@ $(general_service_contexts.tmp): $(addprefix $(LOCAL_PATH)/, service_contexts)
 $(LOCAL_BUILT_MODULE): PRIVATE_SEPOLICY := $(built_general_sepolicy)
 $(LOCAL_BUILT_MODULE): $(general_service_contexts.tmp) $(built_general_sepolicy) $(HOST_OUT_EXECUTABLES)/checkfc $(ACP)
 	@mkdir -p $(dir $@)
-	$(hide) $(HOST_OUT_EXECUTABLES)/checkfc -s $(PRIVATE_SEPOLICY) $<
-	$(hide) $(ACP) $< $@
+	sed -e 's/#.*$$//' -e '/^$$/d' $< > $@
+	$(hide) $(HOST_OUT_EXECUTABLES)/checkfc -s $(PRIVATE_SEPOLICY) $@
 
 general_service_contexts.tmp :=