Auto merge of #20315 - kwonoj:feat-webrender-capture, r=jdm

feat(window): bind hotkey to trigger capture event

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Relates to #20295.

This PR intends to expose additional hotkey to window to allow capture webrender. Internally it adds one new `WindowEvent::CaptureWebRender` for those purpose. I took some liberty to make some decisions around which need to be reviewed & updated in PR.

- `Ctrl-shift-3` is binded to hotkey to follow described in Gecko's behavior. Is it good to go?
- Maybe do not need to create new event `CaptureWebRender` but reuse `ToggleWebRenderDebug`, having additional `WebRenderDebugOption` values?
: This sounds more right path for me, but `capture` isn't really `toggle` behavior to include capture into it.
- Capturing will create `capture_webrender` in cwd, creates new folder inside each time new capture stored
: Maybe it'd better to expose new cmdline args allow overrides, or some better way else. I took the simple approach to generate path without asking for it.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #20295 (github issue number if applicable).

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1 files changed, 4 insertions, 0 deletions

diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index 45b6af50c89..f5ebed9f04d 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -333,6 +333,10 @@ impl<Window> Servo<Window> where Window: WindowMethods + 'static {
                 self.compositor.toggle_webrender_debug(option);
             }
 
+            WindowEvent::CaptureWebRender => {
+                self.compositor.capture_webrender();
+            }
+
             WindowEvent::NewBrowser(url, response_chan) => {
                 let msg = ConstellationMsg::NewBrowser(url, response_chan);
                 if let Err(e) = self.constellation_chan.send(msg) {