chromium/generate_license_list.py: Check whether the license file exist

With newer Chromium versions, most of the licenses returned by
find_chromium_licenses() are missing from the tarball.

Check whether the file exists to avoid throwing an exception
in open(license_file, 'rb').

Signed-off-by: Zoltán Böszörményi <zboszor@gmail.com>

Author: zboszor

meta-chromium/recipes-browser/chromium/generate_license_list.py

@@ -93,6 +93,8 @@ def print_license_list(chromium_root, output_file):
     suitable for use in a Yocto recipe."""
     licenses = {}
     for license_file in find_chromium_licenses(chromium_root):
+        if not os.path.exists(license_file):
+            continue
         with open(license_file, 'rb') as file_handle:
             license_hash = hashlib.md5(file_handle.read()).hexdigest()
         license_relpath = os.path.relpath(license_file, chromium_root)