Implement setting position through webdriver for headed window (#38209)

Previously, we pretend we are able to set position in response. Now we
can really do it.

Testing: Able to set position accurately when tested locally.
Fixes: Task 5 of #37804.

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Signed-off-by: Euclid Ye <euclid.ye@huawei.com>

components/constellation/constellation.rs

@@ -4461,7 +4461,7 @@ where
             WebDriverCommandMsg::IsWebViewOpen(..) |
             WebDriverCommandMsg::GetWindowRect(..) |
             WebDriverCommandMsg::GetViewportSize(..) |
-            WebDriverCommandMsg::SetWindowSize(..) |
+            WebDriverCommandMsg::SetWindowRect(..) |
             WebDriverCommandMsg::LoadUrl(..) |
             WebDriverCommandMsg::Refresh(..) |
             WebDriverCommandMsg::SendKeys(..) |