Remove the --explicit-src-files from recursive-lipo

This option has been subsumed by the improved semantics of
`--copy-subdirs`.

Author: DougGregor

utils/build-script-impl

@@ -3579,7 +3579,7 @@ if [[ ${#LIPO_SRC_DIRS[@]} -gt 0 ]]; then
         else
             LIPO_PATH="${HOST_LIPO}"
         fi
-        call "${SWIFT_SOURCE_DIR}"/utils/recursive-lipo --lipo=${LIPO_PATH} --copy-subdirs="$(get_host_install_prefix ${host})lib/swift $(get_host_install_prefix ${host})lib/swift_static" --explicit-src-files="$(get_host_install_prefix ${host})lib/swift/${host%%-*}/lib_InternalSwiftScan.dylib" --destination="$(get_host_install_destdir ${mergedHost})" ${LIPO_SRC_DIRS[@]}
+        call "${SWIFT_SOURCE_DIR}"/utils/recursive-lipo --lipo=${LIPO_PATH} --copy-subdirs="$(get_host_install_prefix ${host})lib/swift $(get_host_install_prefix ${host})lib/swift_static" --destination="$(get_host_install_destdir ${mergedHost})" ${LIPO_SRC_DIRS[@]}
 
         if [[ $(should_execute_action "${mergedHost}-lipo") ]]; then
             # Build and test the lipo-ed package.

utils/recursive-lipo

@@ -9,12 +9,10 @@ import shutil
 from swift_build_support.swift_build_support import shell
 
 
-def merge_file_lists(src_root_dirs, explicit_src_files, skip_files,
-                     skip_subpaths):
+def merge_file_lists(src_root_dirs, skip_files):
     """Merges the file lists recursively from all src_root_dirs supplied,
     returning the union of all file paths found.
     Files matching skip_files are ignored and skipped.
-    Subpaths matching skip_subpaths are not recursed into.
     """
     file_list = []
     for src_root_dir in src_root_dirs:
@@ -25,15 +23,7 @@ def merge_file_lists(src_root_dirs, explicit_src_files, skip_files,
                 if file not in skip_files]
             file_list.extend(
                 filter(lambda file: file not in file_list, rel_files))
-            dirs[:] = filter(
-                lambda dir: os.path.join(rel_dir, dir)
-                not in skip_subpaths, dirs)
-
-    for file in explicit_src_files:
-        # If this is an absolute installation path, e.g. /Applications/Xcode/...,
-        # treat it as being relative to a built toolchain
-        relative_path = file[1:] if file.startswith("/") else file
-        file_list.append(relative_path) if relative_path not in file_list else file_list
+
     return file_list
 
 
@@ -173,15 +163,6 @@ binaries.
                         default=".DS_Store",
                         help="Files to ignore and skip merge/copy, default " +
                              "is \".DS_Store\"")
-    # A list of files which this script will ensure are merged using lipo.
-    # The intent is to allow for exceptions to binaries located under
-    # `copy-subdirs` that are not built fat. However, if more such exceptions
-    # are added, it would be better to re-think our approach to a more-general
-    # solution.
-    parser.add_argument("--explicit-src-files", metavar="<explicit-source-files>",
-                        default="",
-                        help="Optional list of files which should be merged to " +
-                             "be installed")
     parser.add_argument("--copy-subdirs", metavar="<subdirs-to-copy-verbatim>",
                         default="",
                         help="Optional list of subdirectory paths that " +
@@ -198,12 +179,10 @@ binaries.
     args = parser.parse_args()
 
     skip_files = args.skip_files.split()
-    explicit_sources = args.explicit_src_files.split()
     copy_verbatim_subpaths = [
         subdir.strip('/') for subdir in args.copy_subdirs.split()]
 
-    file_list = merge_file_lists(args.src_root_dirs, explicit_sources,
-                                 skip_files, ())
+    file_list = merge_file_lists(args.src_root_dirs, skip_files)
 
     if args.verbose:
         print("Discovered files and dirs: %s" % file_list)