Implement full page screenshot for Chrome

[k7z45]

🚀 Feature Proposal

ChromeDriver implemented full page screenshot end point similar to geckodriver in ChromeDriver 86.0.4240.22 CL (https://chromium-review.googlesource.com/c/chromium/src/+/2300980).
Selenium can utilize the endpoint to implement full page screenshot feature.

There is a proposal at w3c/webdriver#1536 for adding it to WebDriver standards.
Since gecko already supports it, I think we can add it for Chrome as well.

Motivation

Highly sought after in https://bugs.chromium.org/p/chromedriver/issues/detail?id=294#c161.

Example

The ChromeDriver endpoint is Get request at /session/:sessionId/screenshot/full

[diemol]

@k7z45 this is part of #8168, I will close this as a duplicate.

[k7z45]

@diemol BiDi should not be a dependency for this feature. Firefox already implements this feature. ChromeDriver can now supports full page screenshot through endpoint /session/:sessionId/screenshot/full in version 86. It can be available to user if Selenium makes use of it.

[diemol]

The linked issue is not about implementing BiDi, is about defining an API, that initially works with CDP (which is the work being done for Selenium 4).

[k7z45]

Agh, gotcha. Thanks for the clarification!