extract-utils: Apply relative path for apps with deep folder structures

While most apps follow the standard structure of <partition>/app/<app_name>/<app_name>.apk
or <partition>/priv-app/<app_name>/<app_name>.apk, some apps require deeper directory
structures, such as Android Platform Services which belongs in
product/priv-app/GmsCore/m/independent/AndroidPlatformServices.apk.

Without this change, such apps would be incorrectly copied to
product/priv-app/AndroidPlatformServices/AndroidPlatformServices.apk, losing their
proper directory structure.

Bash implementation: AOSPA/android_tools_extract-utils@d6a5704

Change-Id: Ia44df744841b2a83f9c02733cb0bb7d0898a5b94
Signed-off-by: Jyotiraditya Panda <jyotiraditya@aospa.co>

Author: imjyotiraditya

extract_utils/bp_builder.py

@@ -162,17 +162,20 @@ def __init__(
 
         self.set_partition(file.partition)
 
-    def __file_dir_without_prefix(self) -> Optional[str]:
+    def __file_dir_without_prefix(self, is_app=False) -> Optional[str]:
         # Remove the length of the file tree prefix from the dirname,
         # including the final slash
         remaining = self.__file.dirname[self.__prefix_len :]
         if not remaining:
             return None
 
+        if is_app and '/' not in remaining:
+            return None
+
         return remaining
 
-    def relative_install_path(self):
-        p = self.__file_dir_without_prefix()
+    def relative_install_path(self, is_app=False):
+        p = self.__file_dir_without_prefix(is_app)
         return self.set('relative_install_path', p, optional=True)
 
     def sub_dir(self):

extract_utils/makefiles.py

@@ -343,6 +343,7 @@ def write_app_package(file: File, builder: FileBpBuilder):
         .set('dex_preopt', {'enabled': False})
         .set('privileged', file.privileged, optional=True)
         .skip_preprocessed_apk_checks()
+        .relative_install_path(is_app=True)
         .specific()
     )
     return package_name