Auto merge of #23581 - georgeroman:implement_get_page_source_wd_command, r=jdm

Implement GetPageSource WebDriver command

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- [X] `./mach test-tidy` does not report any errors

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- [X] There are tests for these changes

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2 files changed, 30 insertions, 0 deletions

diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 9264b7b9312..b81ff6d5fc7 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -1902,6 +1902,9 @@ impl ScriptThread {
             WebDriverScriptCommand::GetActiveElement(reply) => {
                 webdriver_handlers::handle_get_active_element(&*documents, pipeline_id, reply)
             },
+            WebDriverScriptCommand::GetPageSource(reply) => {
+                webdriver_handlers::handle_get_page_source(&*documents, pipeline_id, reply)
+            },
             WebDriverScriptCommand::GetCookies(reply) => {
                 webdriver_handlers::handle_get_cookies(&*documents, pipeline_id, reply)
             },
diff --git a/components/script/webdriver_handlers.rs b/components/script/webdriver_handlers.rs
index 81f45283c9a..5574451bd5b 100644
--- a/components/script/webdriver_handlers.rs
+++ b/components/script/webdriver_handlers.rs
@@ -10,6 +10,7 @@ use crate::dom::bindings::codegen::Bindings::HTMLInputElementBinding::HTMLInputE
 use crate::dom::bindings::codegen::Bindings::HTMLOptionElementBinding::HTMLOptionElementMethods;
 use crate::dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
 use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
+use crate::dom::bindings::codegen::Bindings::XMLSerializerBinding::XMLSerializerMethods;
 use crate::dom::bindings::conversions::{
     ConversionResult, FromJSValConvertible, StringificationBehavior,
 };
@@ -24,6 +25,7 @@ use crate::dom::htmlinputelement::HTMLInputElement;
 use crate::dom::htmloptionelement::HTMLOptionElement;
 use crate::dom::node::{window_from_node, Node, ShadowIncluding};
 use crate::dom::window::Window;
+use crate::dom::xmlserializer::XMLSerializer;
 use crate::script_thread::Documents;
 use cookie::Cookie;
 use euclid::{Point2D, Rect, Size2D};
@@ -281,6 +283,31 @@ pub fn handle_get_active_element(
         .unwrap();
 }
 
+pub fn handle_get_page_source(
+    documents: &Documents,
+    pipeline: PipelineId,
+    reply: IpcSender<Result<String, ()>>,
+) {
+    reply
+        .send(documents.find_document(pipeline).ok_or(()).and_then(|doc| {
+            match doc.GetDocumentElement() {
+                Some(elem) => match elem.GetOuterHTML() {
+                    Ok(source) => Ok(source.to_string()),
+                    Err(_) => {
+                        match XMLSerializer::new(doc.window())
+                            .SerializeToString(elem.upcast::<Node>())
+                        {
+                            Ok(source) => Ok(source.to_string()),
+                            Err(_) => Err(()),
+                        }
+                    },
+                },
+                None => Err(()),
+            }
+        }))
+        .unwrap();
+}
+
 pub fn handle_get_cookies(
     documents: &Documents,
     pipeline: PipelineId,