Align drag feedback for links with draggable="true" to Safari.

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

 /*
  * Copyright (C) 2007, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 16 matching lines @@
 #include "core/page/DragController.h"
 
 #include "bindings/core/v8/ExceptionStatePlaceholder.h"
 #include "core/HTMLNames.h"
 #include "core/InputTypeNames.h"
 #include "core/clipboard/DataObject.h"
 #include "core/clipboard/DataTransfer.h"
 #include "core/clipboard/DataTransferAccessPolicy.h"
 #include "core/dom/Document.h"
 #include "core/dom/DocumentFragment.h"
 #include "core/dom/DocumentUserGestureToken.h"

[pwnall, 2016/10/29 00:24:24]

This is from a rebase. Sorry, I forgot to upload the rebase separately :(

 #include "core/dom/Element.h"
 #include "core/dom/Node.h"
 #include "core/dom/Text.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/DragCaretController.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/Editor.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/commands/DragAndDropCommand.h"
 #include "core/editing/serializers/Serialization.h"
@@ skipping 189 matching lines @@
 }
 
 DragSession DragController::dragUpdated(DragData* dragData) {
   return dragEnteredOrUpdated(dragData);
 }
 
 bool DragController::performDrag(DragData* dragData) {
   DCHECK(dragData);
   m_documentUnderMouse = m_page->deprecatedLocalMainFrame()->documentAtPoint(
       dragData->clientPosition());
   UserGestureIndicator gesture(DocumentUserGestureToken::create(

[pwnall, 2016/10/29 00:24:24]

This is from a rebase. Sorry, I forgot to upload the rebase separately :(

       m_documentUnderMouse, UserGestureToken::NewGesture));
   if ((m_dragDestinationAction & DragDestinationActionDHTML) &&
       m_documentIsHandlingDrag) {
     LocalFrame* mainFrame = m_page->deprecatedLocalMainFrame();
     bool preventedDefault = false;
     if (mainFrame->view()) {
       // Sending an event can result in the destruction of the view and part.
       DataTransfer* dataTransfer =
           createDraggingDataTransfer(DataTransferReadable, dragData);
       dataTransfer->setSourceOperation(dragData->draggingSourceOperationMask());
@@ skipping 533 matching lines @@
       if (dragMode == DRAG_NONE)
         continue;
       // Even if the image is part of a selection, we always only drag the image
       // in this case.
       if (layoutObject->isImage() && src->settings() &&
           src->settings()->loadsImagesAutomatically()) {
         dragType = DragSourceActionImage;
         return node;
       }
       // Other draggable elements are considered unselectable.
+      if (dragMode == DRAG_ELEMENT) {
+        candidateDragType = DragSourceActionDHTML;
+        break;
+      }
       if (isHTMLAnchorElement(*node) &&
           toHTMLAnchorElement(node)->isLiveLink()) {
         candidateDragType = DragSourceActionLink;
         break;
       }
-      if (dragMode == DRAG_ELEMENT) {
-        candidateDragType = DragSourceActionDHTML;
-        break;
-      }
     }
   }
 
   if (candidateDragType == DragSourceActionNone) {
     // Either:
     // 1) Nothing under the cursor is considered draggable, so we bail out.
     // 2) There was a selection under the cursor but selectionDragPolicy is set
     //    to DelayedSelectionDragResolution and no other draggable element could
     //    be found, so bail out and allow text selection to start at the cursor
     //    instead.
@@ skipping 83 matching lines @@
   Node* node = state.m_dragSrc.get();
 
   if (state.m_dragType == DragSourceActionSelection) {
     dataTransfer->writeSelection(src->selection());
   } else if (state.m_dragType == DragSourceActionImage) {
     if (imageURL.isEmpty() || !node || !node->isElementNode())
       return false;
     Element* element = toElement(node);
     prepareDataTransferForImageDrag(src, dataTransfer, element, linkURL,
                                     imageURL, hitTestResult.altDisplayString());
-  } else if (state.m_dragType == DragSourceActionLink) {
-    if (linkURL.isEmpty())
-      return false;
-    // Simplify whitespace so the title put on the clipboard resembles what the
-    // user sees on the web page. This includes replacing newlines with spaces.
-    dataTransfer->writeURL(node, linkURL,
-                           hitTestResult.textContent().simplifyWhiteSpace());
+  } else {
+    if (isHTMLAnchorElement(*node) && toHTMLAnchorElement(node)->isLiveLink() &&

[dcheng, 2016/10/31 22:31:35]

I was thinking we could make this a top-level if () with no else--it's default
behavior we want as long as the dragged node is a link, right? Or do we not want
this behavior if the link being dragged only contains an image? (I don't quite
remember how this case resolves itself)

[pwnall, 2016/11/04 23:08:29]

Done.
I'll learn about this more as I work through the feedback bugs and the image
bugs :D

+        !linkURL.isEmpty()) {
+      // Simplify whitespace so the title put on the clipboard resembles what
+      // the user sees on the web page. This includes replacing newlines with
+      // spaces.
+      dataTransfer->writeURL(node, linkURL,
+                             hitTestResult.textContent().simplifyWhiteSpace());
+    }
+
+    if (state.m_dragType == DragSourceActionLink) {
+      if (linkURL.isEmpty())
+        return false;
+    } else if (state.m_dragType == DragSourceActionDHTML) {
+      if (LayoutObject* layoutObject = node->layoutObject()) {
+        IntRect boundingIncludingDescendants =
+            layoutObject->absoluteBoundingBoxRectIncludingDescendants();
+        IntSize delta = dragOrigin - boundingIncludingDescendants.location();
+        dataTransfer->setDragImageElement(node, IntPoint(delta));
+      } else {
+        // The layoutObject has disappeared, this can happen if the onStartDrag
+        // handler has hidden the element in some way. In this case we just kill
+        // the drag.
+        return false;
+      }
+
+      // FIXME: For DHTML/draggable element drags, write element markup to
+      // clipboard.
+    }
   }
-  // FIXME: For DHTML/draggable element drags, write element markup to
-  // clipboard.
   return true;
 }
 
 static IntPoint dragLocationForDHTMLDrag(const IntPoint& mouseDraggedPoint,
                                          const IntPoint& dragOrigin,
                                          const IntPoint& dragImageOffset,
                                          bool isLinkImage) {
   // dragImageOffset is the cursor position relative to the lower-left corner of
   // the image.
   const int yOffset = -dragImageOffset.y();
@@ skipping 281 matching lines @@
 }
 
 DEFINE_TRACE(DragController) {
   visitor->trace(m_page);
   visitor->trace(m_documentUnderMouse);
   visitor->trace(m_dragInitiator);
   visitor->trace(m_fileInputElementUnderMouse);
 }
 
 }  // namespace blink