Co-authored-by: Renzo Olivares <roliv@google.com>

Revert "Disable cursor opacity animation on macOS, make iOS cursor animation discrete (#104335)" (#106762)

Bug fix for focusing a field with right click on existing selection (Mac and iOS)

* Add tests

* fix tests

* updates
Co-authored-by: Renzo Olivares <roliv@google.com>

* Revert "Add default selection style (#100719)"

This reverts commit c8057bc5.

* update

* update

This reverts commit c74a646b.

* Clean up ClipboardStatusNotifier

* fix

* fix test

* more refactaaaaagit add .

* Unify Text selection API

* fix test

* further simplify

* fix more tests

* styling change

Supports the desktop text editing interaction of holding shift, tapping the field, and dragging to modify the selection.

This reverts commit c54ce015.

Before this change, it was possible to select and copy obscured text from a text field.

This  changes things so that:
- Obscured text fields don't allow copy or cut.
- If a field is both obscured and read-only, then selection is disabled as well (if you can't modify it, and can't copy it, there's no point in selecting it).

This reverts commit 5fd259be.

Simplifying and refactoring parts of RenderEditable. Functionality is the same.