Make protobuf.gyp compatible with Probobuf v25.0

This is a preparation to update Protobuf to v25.0 (#841).

With this commit, protobuf.gyp becomes compatible with both v24.2 and
v25.0.

Note that Protobuf version is not yet updated in this commit.
Thus there must be no observable behavior change.

PiperOrigin-RevId: 579739765

src/protobuf/protobuf.gyp

@@ -75,9 +75,9 @@
     ],
     # Sources for protoc (common part and C++ generator only).
     'protoc_sources': [
-      '<!@(<(glob_protobuf) compiler "*.cc" --exclude "*_tester.cc" fake_plugin.cc main.cc)',
+      '<!@(<(glob_protobuf) compiler "*.cc" --exclude "*_tester.cc" fake_plugin.cc test_plugin.cc main.cc)',
       '<!@(<(glob_protobuf) compiler/allowlists "*.cc")',
-      '<!@(<(glob_protobuf) compiler/cpp "**/*.cc")',
+      '<!@(<(glob_protobuf) compiler/cpp "**/*.cc" --exclude main.cc)',
       'custom_protoc_main.cc',
     ],
   },
@@ -122,6 +122,13 @@
           'msvs_disabled_warnings': [
             '<@(msvc_disabled_warnings_for_protoc)',
           ],
+          'msvs_settings': {
+            'VCCLCompilerTool': {
+              'AdditionalOptions': [
+                '/permissive',  # https://github.com/protocolbuffers/protobuf/issues/14602
+              ],
+            },
+          },
           'xcode_settings': {
             'USE_HEADERMAP': 'NO',
           },