Fix build file such that CarSystemUi can be easily extended

This is done buy building all of CarSystemUI as a library and then including that
library as a static lib for an android_app target. Thus anyone that wants to
build a derivative to CarSystemUI can include that library and start extending.
It is the same mechanism that allows CarSystemUI to extend the phone SystemUI

Bug:140875212

Test: Build and Deploy
Change-Id: I4c83b0147c5ce8a8b4321ba0866721e4922df431

packages/CarSystemUI/Android.bp

@@ -13,18 +13,19 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
-android_app {
-    name: "CarSystemUI",
-
-    overrides: [
-        "SystemUI",
-    ],
+android_library {
+    name: "CarSystemUI-core",
 
     srcs: [
         "src/**/*.java",
         "src/**/I*.aidl",
     ],
 
+    resource_dirs: [
+        "res-keyguard",
+        "res",
+    ],
+
     static_libs: [
         "SystemUI-core",
         "CarNotificationLib",
@@ -58,6 +59,28 @@ android_app {
 
     manifest: "AndroidManifest.xml",
 
+    plugins: ["dagger2-compiler-2.19"],
+
+}
+
+android_app {
+    name: "CarSystemUI",
+
+    static_libs: [
+        "CarSystemUI-core",
+    ],
+
+    libs: [
+        "telephony-common",
+        "android.car",
+    ],
+
+    resource_dirs: [],
+
+     overrides: [
+        "SystemUI",
+    ],
+
     platform_apis: true,
     product_specific: true,
     certificate: "platform",
@@ -68,12 +91,6 @@ android_app {
             "proguard.flags",
         ],
     },
-    resource_dirs: [
-        "res-keyguard",
-        "res",
-    ],
-
-
     dxflags: ["--multi-dex"],
 
     aaptflags: [
@@ -81,6 +98,8 @@ android_app {
         "com.android.keyguard",
     ],
 
+    kotlincflags: ["-Xjvm-default=enable"],
+
     plugins: ["dagger2-compiler-2.19"],
 
     required: ["privapp_whitelist_com.android.systemui"],