Auto merge of #8151 - jgraham:webdriver_sendkeys, r=jgraham

Implement support for WebDriver send keys command.

Supports sending keys to an element. The specification here is still
rather unfinished so the error handling and so on in this code will
need iteration as it becomes clearer what the expected behaviour is.

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components/script/script_task.rs

@@ -1086,6 +1086,8 @@ impl ScriptTask {
                 webdriver_handlers::handle_find_element_css(&page, pipeline_id, selector, reply),
             WebDriverScriptCommand::FindElementsCSS(selector, reply) =>
                 webdriver_handlers::handle_find_elements_css(&page, pipeline_id, selector, reply),
+            WebDriverScriptCommand::FocusElement(element_id, reply) =>
+                webdriver_handlers::handle_focus_element(&page, pipeline_id, element_id, reply),
             WebDriverScriptCommand::GetActiveElement(reply) =>
                 webdriver_handlers::handle_get_active_element(&page, pipeline_id, reply),
             WebDriverScriptCommand::GetElementTagName(node_id, reply) =>

components/script/webdriver_handlers.rs

@@ -4,6 +4,7 @@
 
 use dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
 use dom::bindings::codegen::Bindings::ElementBinding::ElementMethods;
+use dom::bindings::codegen::Bindings::HTMLElementBinding::HTMLElementMethods;
 use dom::bindings::codegen::Bindings::HTMLIFrameElementBinding::HTMLIFrameElementMethods;
 use dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
 use dom::bindings::codegen::Bindings::NodeListBinding::NodeListMethods;
@@ -11,6 +12,7 @@ use dom::bindings::conversions::{FromJSValConvertible, StringificationBehavior};
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::Root;
 use dom::element::Element;
+use dom::htmlelement::HTMLElement;
 use dom::htmliframeelement::HTMLIFrameElement;
 use dom::node::Node;
 use dom::window::ScriptHelpers;
@@ -147,6 +149,25 @@ pub fn handle_find_elements_css(page: &Rc<Page>,
     }).unwrap();
 }
 
+pub fn handle_focus_element(page: &Rc<Page>,
+                            pipeline: PipelineId,
+                            element_id: String,
+                            reply: IpcSender<Result<(), ()>>) {
+    reply.send(match find_node_by_unique_id(page, pipeline, element_id) {
+        Some(ref node) => {
+            match node.downcast::<HTMLElement>() {
+                Some(ref elem) => {
+                    // Need a way to find if this actually succeeded
+                    elem.Focus();
+                    Ok(())
+                }
+                None => Err(())
+            }
+        },
+        None => Err(())
+    }).unwrap();
+}
+
 pub fn handle_get_active_element(page: &Rc<Page>,
                                  _pipeline: PipelineId,
                                  reply: IpcSender<Option<String>>) {