Do not send redundant selectionchange-events (decouple focus)

third_party/WebKit/Source/core/editing/EditingUtilities.cpp

Index: third_party/WebKit/Source/core/editing/EditingUtilities.cpp
diff --git a/third_party/WebKit/Source/core/editing/EditingUtilities.cpp b/third_party/WebKit/Source/core/editing/EditingUtilities.cpp
index 736d889bf286020e88b7afa6ef2f399bf276d8fd..a443f6a49abd8cd8f4e67c0fca612c473b8621e1 100644
--- a/third_party/WebKit/Source/core/editing/EditingUtilities.cpp
+++ b/third_party/WebKit/Source/core/editing/EditingUtilities.cpp
@@ -374,6 +374,23 @@ Element* rootEditableElement(const Node& node) {
   return toElement(const_cast<Node*>(result));
 }
 
+bool selectionHasFocus(const LocalFrame& frame,

[yosin_UTC9, 2017/03/22 05:07:59]

Let's take Document from selection instead of extra parameter |frame|.

[hugoh_UTC2, 2017/03/22 07:50:33]

SelectionTemplate currently keeps Document private but sure, we can make it
public.

[yosin_UTC9, 2017/03/22 07:53:19]

You can get Document by Position, e.g. selection.base().document()

[hugoh_UTC2, 2017/03/22 08:32:38]

Done. See PS25.

+                       const SelectionInFlatTree& selection) {
+  const Element* focus = frame.document()->focusedElement();
+  if (!focus) {
+    // No focused element means document root has focus.
+    focus = frame.document()->documentElement();
+  }
+
+  const Node* const nodeWhereSelectionStarts =
+      selection.base().computeContainerNode();
+  const Node* const nodeWhereSelectionEnds =
+      selection.extent().computeContainerNode();
+
+  return focus->containsIncludingHostElements(*nodeWhereSelectionStarts) ||
+         focus->containsIncludingHostElements(*nodeWhereSelectionEnds);
+}
+
 ContainerNode* highestEditableRoot(
     const Position& position,
     Element* (*rootEditableElementOf)(const Position&),