Add contextmenu attribute for HTMLElement.

LayoutTests/fast/dom/HTMLElement/contextmenu-expected.txt

Index: LayoutTests/fast/dom/HTMLElement/contextmenu-expected.txt
diff --git a/LayoutTests/fast/dom/HTMLElement/contextmenu-expected.txt b/LayoutTests/fast/dom/HTMLElement/contextmenu-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..30d4ca947cd6a93f58c0d08f06de40fa84d96e11
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+++ b/LayoutTests/fast/dom/HTMLElement/contextmenu-expected.txt
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+Tests the contextmenu attribute.
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+Test with valid contextmenu attribute
+PASS document.getElementById('container1').contextMenu.id is "menu1"
+PASS document.getElementById('container1').contextMenu.type is "popup"
+PASS document.getElementById('container1').contextMenu.label is "menu 1"
+Test with invalid contextmenu attribute
+PASS document.getElementById('container2').contextMenu is null
+Test setting contextmenu attribute
+PASS container3.contextMenu.id is "menu3"
+PASS container3.contextMenu.type is "popup"
+PASS container3.contextMenu.label is "menu 3"
+Test setting contextmenu attribute with menu element without id
+PASS container4.contextMenu is null
+Test setting contextmenu attribute with multiple menu element with same id
+PASS container5.contextMenu is null
+Test setting contextmenu attribute to null
+PASS container6.contextMenu is null
+Test setting contextmenu attribute to some text
+PASS container7.contextMenu is null
+Test setting contextmenu attribute to comment
+PASS container8.contextMenu is null
+Test setting contextmenu attribute to menu without type
+PASS container9.contextMenu.id is "menu_without_type"
+PASS container9.contextMenu.type is ""
+PASS container9.contextMenu.label is "menu without type"
+Test setting contextmenu attribute to menu element which is in shadow dom
+PASS container10.contextMenu is null
+PASS successfullyParsed is true
+
+TEST COMPLETE
+