Add copyright line when importing Analytics iOS headers, if missing (#780)

* Add copyright line to iOS headers

* Make copyright conditional to whether the file already has one.

Author: jonsimantov

.github/workflows/update-dependencies.yml

@@ -108,8 +108,14 @@ jobs:
               for ios_header in *.h; do
                 # Each file in this directory matches a file in the Analytics iOS SDK.
                 cp -vf "${podtmp}/${header_dir}/${ios_header}" .
+                # If the file doesn't have a Google copyright, add one.
+                if ! grep -q "^// Copyright [0-9]* Google LLC" "${ios_header}"; then
+                  copyright_line="// Copyright $(date +%Y) Google LLC\n"
+                else
+                  copyright_line=
+                fi
                 # Add a note to each file about its source.
-                sed -i~ 's|^/// @file|\n// Copied from Firebase Analytics iOS SDK '"${analytics_version}"'.\n\n/// @file|' "${ios_header}"
+                sed -i~ "s|^/// @file|${copyright_line}\n// Copied from Firebase Analytics iOS SDK ${analytics_version}.\n\n/// @file|" "${ios_header}"
                 rm -f "${ios_header}~" # remove backup file that sed generated
                 python ../../scripts/format_code.py --f "${ios_header}"
               done