Convert signapk to Android.bp

See build/soong/README.md for more information

Test: m checkbuild
Change-Id: I89a7fa7647e7081ca49720fae3be23ce84ab38e5
diff --git a/tools/signapk/Android.bp b/tools/signapk/Android.bp
new file mode 100644
index 0000000..4954cf5
--- /dev/null
+++ b/tools/signapk/Android.bp
@@ -0,0 +1,31 @@
+//
+// Copyright (C) 2008 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+// the signapk tool (a .jar application used to sign packages)
+// ============================================================
+java_library_host {
+    name: "signapk",
+    srcs: ["src/**/*.java"],
+    manifest: "SignApk.mf",
+    static_libs: [
+        "apksig",
+        "bouncycastle",
+        "bouncycastle-bcpkix",
+        "conscrypt",
+    ],
+
+    required: ["libconscrypt_openjdk_jni"],
+}
diff --git a/tools/signapk/Android.mk b/tools/signapk/Android.mk
index 8082842..ff54d6d 100644
--- a/tools/signapk/Android.mk
+++ b/tools/signapk/Android.mk
@@ -15,24 +15,10 @@
 #
 LOCAL_PATH := $(call my-dir)
 
-# the signapk tool (a .jar application used to sign packages)
-# ============================================================
-include $(CLEAR_VARS)
-LOCAL_MODULE := signapk
-LOCAL_SRC_FILES := $(call all-java-files-under, src)
-LOCAL_JAR_MANIFEST := SignApk.mf
-LOCAL_STATIC_JAVA_LIBRARIES := \
-    apksig \
-    bouncycastle \
-    bouncycastle-bcpkix \
-    conscrypt
-LOCAL_REQUIRED_MODULES := libconscrypt_openjdk_jni
-include $(BUILD_HOST_JAVA_LIBRARY)
-
 ifeq ($(TARGET_BUILD_APPS),)
 # The post-build signing tools need signapk.jar and its shared libraries,
 # but we don't need this if we're just doing unbundled apps.
-my_dist_files := $(LOCAL_INSTALLED_MODULE) \
+my_dist_files := $(HOST_OUT_JAVA_LIBRARIES)/signapk.jar \
     $(HOST_OUT_SHARED_LIBRARIES)/libconscrypt_openjdk_jni$(HOST_SHLIB_SUFFIX)
 
 $(call dist-for-goals,droidcore,$(my_dist_files))