* refactor: BaseWindow::OnExecuteAppCommand() now takes a std::string_view
* refactor: NativeWindow::NotifyWindowExecuteAppCommand() takes a std::string_view
* refactor: AppCommandToString() returns a std::string_view, is now constexpr
* refactor: make kBrowserBackward, kBrowserForward inline constexpr std::string_view
Xref: https://abseil.io/tips/140https://groups.google.com/a/chromium.org/g/chromium-dev/c/jROTxMo_m2Q/m/HgciN2KsAgAJ
* refactor: use inline constexpr string_view for kDevice*Key constants
Xref: https://abseil.io/tips/140https://groups.google.com/a/chromium.org/g/chromium-dev/c/jROTxMo_m2Q/m/HgciN2KsAgAJ
* refactor: IsEnvSet now takes a base::cstring_view
* refactor: use inline constexpr cstring_view for kRunAsNode
* refactor: use inline constexpr string_view for kPDF*PluginName
* refactor: use base::FilePath::FromASCII() since "internal-pdf-viewer" is ascii
* chore: remove unused shell/common/electron_constants.cc
* fixup! refactor: IsEnvSet now takes a base::cstring_view