Devtools[LayoutEditor]: Rework layout-editor workflow

Source/devtools/protocol.json

Index: Source/devtools/protocol.json
diff --git a/Source/devtools/protocol.json b/Source/devtools/protocol.json
index 5eb716fe0edb8d32c669ab07e7033caeb1db7c86..9b41ab6f5ceeed4de810cf9b7e229237484a0da7 100644
--- a/Source/devtools/protocol.json
+++ b/Source/devtools/protocol.json
@@ -2518,7 +2518,7 @@
                 "hidden": true,
                 "parameters": [
                     { "name": "enabled", "type": "boolean", "description": "True to enable inspection mode, false to disable it." },
-                    { "name": "inspectUAShadowDOM", "type": "boolean", "optional": true, "description": "True to enable inspection mode for user agent shadow DOM." },
+                    { "name": "mode", "type": "string", "enum": ["showUAShadowDOM", "showLayoutEditor"], "optional": true, "description": "True to enable inspection mode for user agent shadow DOM." },
                     { "name": "highlightConfig", "$ref": "HighlightConfig", "optional": true, "description": "A descriptor for the highlight appearance of hovered-over nodes. May be omitted if <code>enabled == false</code>." }
                 ],
                 "description": "Enters the 'inspect' mode. In this mode, elements that user is hovering over are highlighted. Backend then generates 'inspectNodeRequested' event upon element selection."