Move libartpalette-system to system/libartpalette

Bug: 142944508
Test: art/tools/buildbot-build.sh --host && art/test/test.py --host -r -g
Test: art/tools/buildbot-build.sh --target && art/test/test.py --target -r -g
Change-Id: Ia04ce022fa91d2ac6c9b5046e301a9a6ba10a852
diff --git a/libartpalette/Android.bp b/libartpalette/Android.bp
index 0a45b88..f25501d 100644
--- a/libartpalette/Android.bp
+++ b/libartpalette/Android.bp
@@ -21,40 +21,11 @@
     export_include_dirs: ["include"],
 }
 
-// libartpalette-system is the implementation of the abstraction layer. It is
-// only available as a shared library on Android.
-art_cc_library {
-    name: "libartpalette-system",
-    defaults: ["libartpalette_defaults"],
-    compile_multilib: "both",
-    target: {
-        android: {
-            srcs: ["system/palette_android.cc"],
-            header_libs: ["libbase_headers"],
-            shared_libs: [
-                "libbase",
-                "libcutils",
-                "liblog",
-                "libprocessgroup",
-                "libtombstoned_client",
-            ],
-        },
-        host: {
-            header_libs: ["libbase_headers"],
-            srcs: ["system/palette_fake.cc"],
-            shared_libs: ["libbase"],
-        },
-        darwin: {
-            enabled: false,
-        },
-        windows: {
-            enabled: false,
-        },
-    },
-    static: {
-        enabled: false,
-    },
-    version_script: "libartpalette.map.txt",
+cc_library_headers {
+    name: "libartpalette-headers",
+    export_include_dirs: ["include"],
+    host_supported: true,
+    visibility: ["//system/libartpalette"],
 }
 
 // libartpalette is the dynamic loader of the platform abstraction