GN(android): Add scripts & runtime logic for installing _managed apks

build/config/android/internal_rules.gni

Index: build/config/android/internal_rules.gni
diff --git a/build/config/android/internal_rules.gni b/build/config/android/internal_rules.gni
index 613cb077ff43b074f7d45a483bc7b7d026467806..f974812c0c703d065e130c4a62a08047f9623783 100644
--- a/build/config/android/internal_rules.gni
+++ b/build/config/android/internal_rules.gni
@@ -1226,9 +1226,7 @@ template("java_library_impl") {
   }
 
   _java_files = []
-  if (defined(invoker.java_files)) {
-    _java_files = invoker.java_files
-  } else if (defined(invoker.DEPRECATED_java_in_dir)) {
+  if (defined(invoker.DEPRECATED_java_in_dir)) {
     _src_dir = invoker.DEPRECATED_java_in_dir + "/src"
     _src_dir_exists = exec_script("//build/dir_exists.py",
                                   [ rebase_path(_src_dir, root_build_dir) ],
@@ -1237,16 +1235,20 @@ template("java_library_impl") {
            "In GN, java_in_dir should be the fully specified java directory " +
                "(i.e. including the trailing \"/src\")")
 
-    _java_files_build_rel = exec_script(
-            "//build/android/gyp/find.py",
-            [
-              "--pattern",
-              "*.java",
-              rebase_path(invoker.DEPRECATED_java_in_dir, root_build_dir),
-            ],
-            "list lines")
+    _java_files_build_rel =
+        exec_script("//build/android/gyp/find.py",
+                    [
+                      "--pattern",
+                      "*.java",
+                      rebase_path(invoker.DEPRECATED_java_in_dir,
+                                  root_build_dir),
+                    ],
+                    "list lines")
     _java_files = rebase_path(_java_files_build_rel, ".", root_build_dir)
   }
+  if (defined(invoker.java_files)) {
+    _java_files += invoker.java_files
+  }
   assert(_java_files != [] || _srcjar_deps != [] || _srcjars != [])
 
   _compile_java_target = "${_template_name}__compile_java"