Convert libart and dependencies to Android.bp

Re-landing I73839046a5a53eb34cd28eea53149911c568e411, with fixes for mac
build (only apply -Wl,--keep-unique to device x86 builds), typo in
checking for ART_HEAP_POISONING environment variable, and removing
-Wframe-larger-than for debug builds.

Test: mma -j, m -j test-art-host
Change-Id: If88492174cbcb0d9a8758176c006163a29eaaa63
diff --git a/build/makevars.go b/build/makevars.go
new file mode 100644
index 0000000..5655c55
--- /dev/null
+++ b/build/makevars.go
@@ -0,0 +1,30 @@
+// Copyright (C) 2016 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.
+
+package art
+
+import "android/soong/android"
+
+var (
+	pctx = android.NewPackageContext("android/soong/art")
+)
+
+func init() {
+	android.RegisterMakeVarsProvider(pctx, makeVarsProvider)
+}
+
+func makeVarsProvider(ctx android.MakeVarsContext) {
+	ctx.Strict("LIBART_IMG_HOST_BASE_ADDRESS", ctx.Config().LibartImgHostBaseAddress())
+	ctx.Strict("LIBART_IMG_TARGET_BASE_ADDRESS", ctx.Config().LibartImgDeviceBaseAddress())
+}