DevTools: better hasSelection check to include composed trees

third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js

Index: third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js
diff --git a/third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js b/third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js
index 2a2cb03bd15e6062cdea6878f92a303e2264fb94..a2d99dfa65f731160484df196a6927ced45df318 100644
--- a/third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js
+++ b/third_party/WebKit/Source/devtools/front_end/platform/DOMExtension.js
@@ -277,6 +277,12 @@ Node.prototype.isComponentSelectionCollapsed = function() {
  * @return {boolean}
  */
 Node.prototype.hasSelection = function() {
+  // TODO(luoe): use contains(node, {includeShadow: true}) when it is fixed for shadow dom.
+  var contents = this.querySelectorAll('content');
+  for (var content of contents) {
+    if (Array.prototype.some.call(content.getDistributedNodes(), node => node.hasSelection()))
+      return true;
+  }
   if (this.isComponentSelectionCollapsed())
     return false;
   return this.getComponentSelection().containsNode(this, true);