Unify media.codec and media.extractor Minijail usage.

That way we can modify this code in one place to take a list of seccomp
policy files.

This CL removes around 70 lines by unifying identical code. No change
in behavior.

Bug: 34723744
Test: media.codec, media.extractor start, have Seccomp.
Test: cat /proc/`pgrep .codec`/status | grep Seccomp
      Seccomp:    2
Test: cat /proc/`pgrep .extractor`/status | grep Seccomp
      Seccomp:    2
Change-Id: Ia8be7b9c3d6163804d2a45954f8d03315ae32e7a
diff --git a/services/mediaextractor/Android.mk b/services/mediaextractor/Android.mk
index 4e337a0..169c770 100644
--- a/services/mediaextractor/Android.mk
+++ b/services/mediaextractor/Android.mk
@@ -15,8 +15,9 @@
 LOCAL_REQUIRED_MODULES_arm64 := mediaextractor-seccomp.policy
 LOCAL_REQUIRED_MODULES_x86 := mediaextractor-seccomp.policy
 # TODO add seccomp filter for x86_64.
-LOCAL_SRC_FILES := main_extractorservice.cpp minijail/minijail.cpp
-LOCAL_SHARED_LIBRARIES := libmedia libmediaextractorservice libbinder libutils liblog libicuuc libminijail
+LOCAL_SRC_FILES := main_extractorservice.cpp
+LOCAL_SHARED_LIBRARIES := libmedia libmediaextractorservice libbinder libutils \
+    liblog libbase libicuuc libavservices_minijail
 LOCAL_STATIC_LIBRARIES := libicuandroid_utils
 LOCAL_MODULE:= mediaextractor
 LOCAL_INIT_RC := mediaextractor.rc