packaging: bundle the default mercurial.ini template with Inno also

This is a step towards converging on the same installer content on Windows.

Differential Revision: https://phab.mercurial-scm.org/D8061

contrib/packaging/hgpackaging/inno.py

@@ -21,6 +21,7 b' from .py2exe import ('
 from .util import (
     find_vc_runtime_files,
     normalize_windows_version,
+    process_install_rules,
     read_version_py,
 )
 
@@ -31,6 +32,10 b' EXTRA_PACKAGES = {'
     'win32ctypes',
 }
 
+EXTRA_INSTALL_RULES = [
+    ('contrib/win32/mercurial.ini', 'defaultrc/mercurial.rc'),
+]
+
 PACKAGE_FILES_METADATA = {
     'ReadMe.html': 'Flags: isreadme',
 }
@@ -84,6 +89,9 b' def build('
     # Now assemble all the packaged files into the staging directory.
     stage_install(source_dir, staging_dir)
 
+    # We also install some extra files.
+    process_install_rules(EXTRA_INSTALL_RULES, source_dir, staging_dir)
+
     # hg.exe depends on VC9 runtime DLLs. Copy those into place.
     for f in find_vc_runtime_files(vc_x64):
         if f.name.endswith('.manifest'):