Clean up merge_target_files.py.

- Removes functions that can be replaced with one-line external methods
- Moves read_config_list to common alongside similar methods LoadDictionaryFrom*
- Runs pyformat on merge_target_files.py

Bug: 137853921
Test: python -m unittest test_merge_target_files
Test: Using merge_target_files.py to create a merged build, & booting.
Change-Id: I833c1086db41e1374057cc7447fc50d1915734a7
diff --git a/tools/releasetools/test_merge_target_files.py b/tools/releasetools/test_merge_target_files.py
index bca29e5..1b1c725 100644
--- a/tools/releasetools/test_merge_target_files.py
+++ b/tools/releasetools/test_merge_target_files.py
@@ -18,7 +18,7 @@
 
 import common
 import test_utils
-from merge_target_files import (read_config_list, validate_config_lists,
+from merge_target_files import (validate_config_lists,
                                 DEFAULT_FRAMEWORK_ITEM_LIST,
                                 DEFAULT_VENDOR_ITEM_LIST,
                                 DEFAULT_FRAMEWORK_MISC_INFO_KEYS, copy_items,
@@ -83,24 +83,6 @@
     self.assertEqual(
         os.readlink(os.path.join(output_dir, 'a_link.cpp')), 'a.cpp')
 
-  def test_read_config_list(self):
-    framework_item_list_file = os.path.join(self.testdata_dir,
-                                            'merge_config_framework_item_list')
-    framework_item_list = read_config_list(framework_item_list_file)
-    expected_framework_item_list = [
-        'META/apkcerts.txt',
-        'META/filesystem_config.txt',
-        'META/root_filesystem_config.txt',
-        'META/system_manifest.xml',
-        'META/system_matrix.xml',
-        'META/update_engine_config.txt',
-        'PRODUCT/*',
-        'ROOT/*',
-        'SYSTEM/*',
-    ]
-    self.assertEqual(sorted(framework_item_list),
-                     sorted(expected_framework_item_list))
-
   def test_validate_config_lists_ReturnsFalseIfMissingDefaultItem(self):
     framework_item_list = list(DEFAULT_FRAMEWORK_ITEM_LIST)
     framework_item_list.remove('SYSTEM/*')