Add libhwminijail for sandboxing with seccomp filters

This is a partial cherry-pick of the internal change, including just
libhwminijail. The user does not exist in AOSP yet.

Bug: 36453956
Test: mmma hardware/interface/minijail
Merged-In: Iab014ff357b7329085a5e18a92f51838d2c72371
Change-Id: I46b030efba25aac3c09cef9bfb782ecdc7187e70
diff --git a/minijail/Android.mk b/minijail/Android.mk
new file mode 100644
index 0000000..272bb0e
--- /dev/null
+++ b/minijail/Android.mk
@@ -0,0 +1,14 @@
+LOCAL_PATH := $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE := libhwminijail
+LOCAL_PROPRIETARY_MODULE := true
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
+LOCAL_SRC_FILES := HardwareMinijail.cpp
+
+LOCAL_SHARED_LIBRARIES := \
+    libbase \
+    libminijail_vendor
+
+include $(BUILD_SHARED_LIBRARY)