IWebEditingDelegate::webViewDidChangeSelection() should be called when any text selection changes inside a WebView. The Mac code already posts a WebViewDidChangeSelectionNotification when text selection changes.
Created attachment 39705 [details]
After further discussion with Adam Roben, we have agreed that it might be better to just post the WebViewDidChangeSelectionNotification instead of using IWebEditingDelegate.
Created attachment 39709 [details]
Comment on attachment 39709 [details]
> Index: WebKit/win/Interfaces/IWebEditingDelegate.idl
> --- WebKit/win/Interfaces/IWebEditingDelegate.idl (revision 48477)
> +++ WebKit/win/Interfaces/IWebEditingDelegate.idl (working copy)
> @@ -23,6 +23,8 @@
> * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> +cpp_quote("#define WebViewDidChangeSelectionNotification TEXT(\"WebViewDidChangeSelectionNotification\")")
I'd put this in IWebView.idl, to match where it is defined in the Mac API.
Fixed in r48478