linux_aura: Handle the suggested atoms in XdndPosition messages.

GTK applications set the XdndActionList on the source window. Qt does
not and we must take the one suggested action out of the XdndPosition
message instead.

BUG=348312
TEST=Make sure that dragging a file from both Nautilus (default GTK file
manager) and Dolphin (default Qt file manager), to the chrome content
area works.

R=sadrul@chromium.org

Review URL: https://codereview.chromium.org/196403005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@257679 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 30 insertions, 8 deletions

diff --git a/ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.cc b/ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.cc
index 3c14c3c..e7101ac 100644
--- a/ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.cc
+++ b/ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11.cc
@@ -154,6 +154,7 @@ class DesktopDragDropClientAuraX11::X11DragContext :
   // message. If we have that data already, dispatch immediately. Otherwise,
   // delay dispatching until we do.
   void OnStartXdndPositionMessage(DesktopDragDropClientAuraX11* client,
+                                  ::Atom suggested_action,
                                   ::Window source_window,
                                   const gfx::Point& screen_point);
 
@@ -177,6 +178,10 @@ class DesktopDragDropClientAuraX11::X11DragContext :
   int GetDragOperation() const;
 
  private:
+  // Masks the X11 atom |xdnd_operation|'s views representation onto
+  // |drag_operation|.
+  void MaskOpeartion(::Atom xdnd_operation, int* drag_operation) const;
+
   // Overridden from MessagePumpDispatcher:
   virtual uint32_t Dispatch(const base::NativeEvent& event) OVERRIDE;
 
@@ -206,6 +211,10 @@ class DesktopDragDropClientAuraX11::X11DragContext :
   // haven't fetched and put in |fetched_targets_| yet.
   std::vector<Atom> unfetched_targets_;
 
+  // XdndPosition messages have a suggested action. Qt applications exclusively
+  // use this, instead of the XdndActionList which is backed by |actions_|.
+  Atom suggested_action_;
+
   // Possible actions.
   std::vector<Atom> actions_;
 
@@ -220,7 +229,8 @@ DesktopDragDropClientAuraX11::X11DragContext::X11DragContext(
       local_window_(local_window),
       source_window_(event.data.l[0]),
       drag_drop_client_(NULL),
-      waiting_to_handle_position_(false) {
+      waiting_to_handle_position_(false),
+      suggested_action_(None) {
   bool get_types = ((event.data.l[1] & 1) != 0);
 
   if (get_types) {
@@ -273,9 +283,11 @@ DesktopDragDropClientAuraX11::X11DragContext::~X11DragContext() {
 
 void DesktopDragDropClientAuraX11::X11DragContext::OnStartXdndPositionMessage(
     DesktopDragDropClientAuraX11* client,
+    ::Atom suggested_action,
     ::Window source_window,
     const gfx::Point& screen_point) {
   DCHECK_EQ(source_window_, source_window);
+  suggested_action_ = suggested_action;
 
   if (!unfetched_targets_.empty()) {
     // We have unfetched targets. That means we need to pause the handling of
@@ -349,17 +361,25 @@ int DesktopDragDropClientAuraX11::X11DragContext::GetDragOperation() const {
   int drag_operation = ui::DragDropTypes::DRAG_NONE;
   for (std::vector<Atom>::const_iterator it = actions_.begin();
        it != actions_.end(); ++it) {
-    if (*it == atom_cache_->GetAtom(kXdndActionCopy))
-      drag_operation |= ui::DragDropTypes::DRAG_COPY;
-    else if (*it == atom_cache_->GetAtom(kXdndActionMove))
-      drag_operation |= ui::DragDropTypes::DRAG_MOVE;
-    else if (*it == atom_cache_->GetAtom(kXdndActionLink))
-      drag_operation |= ui::DragDropTypes::DRAG_LINK;
+    MaskOpeartion(*it, &drag_operation);
   }
 
+  MaskOpeartion(suggested_action_, &drag_operation);
+
   return drag_operation;
 }
 
+void DesktopDragDropClientAuraX11::X11DragContext::MaskOpeartion(
+    ::Atom xdnd_operation,
+    int* drag_operation) const {
+  if (xdnd_operation == atom_cache_->GetAtom(kXdndActionCopy))
+    *drag_operation |= ui::DragDropTypes::DRAG_COPY;
+  else if (xdnd_operation == atom_cache_->GetAtom(kXdndActionMove))
+    *drag_operation |= ui::DragDropTypes::DRAG_MOVE;
+  else if (xdnd_operation == atom_cache_->GetAtom(kXdndActionLink))
+    *drag_operation |= ui::DragDropTypes::DRAG_LINK;
+}
+
 uint32_t DesktopDragDropClientAuraX11::X11DragContext::Dispatch(
     const base::NativeEvent& event) {
   if (event->type == PropertyNotify &&
@@ -450,6 +470,7 @@ void DesktopDragDropClientAuraX11::OnXdndPosition(
   unsigned long source_window = event.data.l[0];
   int x_root_window = event.data.l[2] >> 16;
   int y_root_window = event.data.l[2] & 0xffff;
+  ::Atom suggested_action = event.data.l[4];
 
   if (!target_current_context_.get()) {
     NOTREACHED();
@@ -459,7 +480,8 @@ void DesktopDragDropClientAuraX11::OnXdndPosition(
   // If we already have all the data from this drag, we complete it
   // immediately.
   target_current_context_->OnStartXdndPositionMessage(
-      this, source_window, gfx::Point(x_root_window, y_root_window));
+      this, suggested_action, source_window,
+      gfx::Point(x_root_window, y_root_window));
 }
 
 void DesktopDragDropClientAuraX11::OnXdndStatus(