feat: implement File System API support (#41827)

* feat: implement File System API support

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* test: add a test for writable permission checking

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* fix: gn check include issues

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* chore: feedback from review

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* chore: cleanup feedback from review

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* refactor: namespace to electron

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* fixup! chore: cleanup feedback from review

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* chore: address more feedback from review

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* 5301485: Add content analysis to File System Access Javascript API.

5301485

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* docs: improve typing of details object

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* chore: address outstanding todo

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* refactor: use Chrome's file system access blocklist

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* lint

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* fix: Windows build

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* test: clarify test verbiage

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

---------

Co-authored-by: trop[bot] <37223003+trop[bot]@users.noreply.github.com>
Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

shell/common/gin_converters/content_converter.cc

@@ -229,6 +229,8 @@ v8::Local<v8::Value> Converter<blink::PermissionType>::ToV8(
       return StringToV8(isolate, "hid");
     case PermissionType::USB:
       return StringToV8(isolate, "usb");
+    case PermissionType::FILE_SYSTEM:
+      return StringToV8(isolate, "fileSystem");
     default:
       return StringToV8(isolate, "unknown");
   }