Do not send redundant selectionchange-events (decouple focus)

third_party/WebKit/Source/core/page/FocusController.cpp

Index: third_party/WebKit/Source/core/page/FocusController.cpp
diff --git a/third_party/WebKit/Source/core/page/FocusController.cpp b/third_party/WebKit/Source/core/page/FocusController.cpp
index 0b5aa3331fc4ac12396ea84b1c09af7ceae97fd5..8065b70f63dbbbd9537c1f1609e78ddce3ec31af 100644
--- a/third_party/WebKit/Source/core/page/FocusController.cpp
+++ b/third_party/WebKit/Source/core/page/FocusController.cpp
@@ -1040,6 +1040,10 @@ bool FocusController::advanceFocusInDocumentOrder(
 
   setFocusedFrame(newDocument.frame());
 
+  if (!element->isTextControl() && !hasEditableStyle(*element->toNode())) {
+    // TODO(editing-dev): Remove this clear(), crbug.com/692898.
+    focusedFrame()->selection().clear();
+  }
   element->focus(
       FocusParams(SelectionBehaviorOnFocus::Reset, type, sourceCapabilities));
   return true;
@@ -1066,35 +1070,6 @@ static bool relinquishesEditingFocus(const Element& element) {
   return element.document().frame() && rootEditableElement(element);
 }
 
-static void clearSelectionIfNeeded(LocalFrame* oldFocusedFrame,
-                                   LocalFrame* newFocusedFrame,
-                                   Element* newFocusedElement) {
-  if (!oldFocusedFrame || !newFocusedFrame)
-    return;
-
-  if (oldFocusedFrame->document() != newFocusedFrame->document())
-    return;
-
-  FrameSelection& selection = oldFocusedFrame->selection();
-  const SelectionInDOMTree& selectionInDOMTree = selection.selectionInDOMTree();
-  if (selectionInDOMTree.isNone())
-    return;
-
-  Node* selectionStartNode = selectionInDOMTree.base().anchorNode();
-  if (selectionStartNode == newFocusedElement ||
-      selectionStartNode->isDescendantOf(newFocusedElement))
-    return;
-
-  if (!enclosingTextControl(selectionStartNode))
-    return;
-
-  if (selectionStartNode->isInShadowTree() &&
-      selectionStartNode->ownerShadowHost() == newFocusedElement)
-    return;
-
-  selection.clear();
-}
-
 bool FocusController::setFocusedElement(Element* element,
                                         Frame* newFocusedFrame) {
   return setFocusedElement(
@@ -1131,10 +1106,6 @@ bool FocusController::setFocusedElement(Element* element,
       newDocument->focusedElement() == element)
     return true;
 
-  if (newFocusedFrame && newFocusedFrame->isLocalFrame())
-    clearSelectionIfNeeded(oldFocusedFrame, toLocalFrame(newFocusedFrame),
-                           element);
-
   if (oldDocument && oldDocument != newDocument)
     oldDocument->clearFocusedElement();
 
@@ -1355,6 +1326,10 @@ bool FocusController::advanceFocusDirectionallyInContainer(
   Element* element = toElement(focusCandidate.focusableNode);
   DCHECK(element);
 
+  if (!element->isTextControl() && !hasEditableStyle(*element->toNode())) {
+    // TODO(editing-dev): Remove this clear(), crbug.com/692898.
+    focusedFrame()->selection().clear();
+  }
   element->focus(FocusParams(SelectionBehaviorOnFocus::Reset, type, nullptr));
   return true;
 }