DevTools: Allow general editing of author shadow DOM elements

LayoutTests/inspector/elements/edit-dom-actions-shadow-expected.txt

Index: LayoutTests/inspector/elements/edit-dom-actions-shadow-expected.txt
diff --git a/LayoutTests/inspector/elements/edit-dom-actions-shadow-expected.txt b/LayoutTests/inspector/elements/edit-dom-actions-shadow-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..062ac885799d9e539b3a8b97f588b29bac3f56ef
--- /dev/null
+++ b/LayoutTests/inspector/elements/edit-dom-actions-shadow-expected.txt
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+Tests that user can mutate author shadow DOM by means of elements panel.
+
+
+Running: testSetUp
+
+Running: testSetAuthorShadowDOMElementAttribute
+==== before ====
+- <div id="testSetAuthorShadowDOMElementAttribute">
+    - #shadow-root
+          <div foo="attribute value" id="shadow-node-to-set-attribute"></div>
+  </div>
+==== after ====
+- <div id="testSetAuthorShadowDOMElementAttribute">
+    - #shadow-root
+          <div id="shadow-node-to-set-attribute" bar="edited attribute"></div>
+  </div>
+
+Running: testEditShadowDOMAsHTML
+==== before ====
+- <div id="testEditAuthorShadowDOMAsHTML">
+    - #shadow-root
+          <div id="authorShadowDOMElement"></div>
+  </div>
+<div id="authorShadowDOMElement"></div>
+==== after ====
+- <div id="testEditAuthorShadowDOMAsHTML">
+    - #shadow-root
+        - <span foo="shadow-span">
+              <span id="inner-shadow-span">Shadow span contents</span>
+          </span>
+  </div>
+