Enable touch-initiated drag-drop work on Windows

content/browser/web_contents/web_drag_source_win.cc

Index: content/browser/web_contents/web_drag_source_win.cc
diff --git a/content/browser/web_contents/web_drag_source_win.cc b/content/browser/web_contents/web_drag_source_win.cc
index 53df4e81725e0984a3f09e7ec496eb022174095f..790c086c283e09a5395c0c970ad4111bdb5bdcb7 100644
--- a/content/browser/web_contents/web_drag_source_win.cc
+++ b/content/browser/web_contents/web_drag_source_win.cc
@@ -6,6 +6,7 @@
 
 #include "base/bind.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
+#include "content/browser/renderer_host/render_widget_host_view_win.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/browser/web_contents/web_drag_utils_win.h"
 #include "content/public/browser/browser_thread.h"
@@ -66,6 +67,7 @@ void WebDragSource::OnDragSourceCancel() {
   web_contents_->DragSourceEndedAt(client.x(), client.y(),
                                    screen.x(), screen.y(),
                                    WebDragOperationNone);
+  OnDragSourceEnded();
 }
 
 void WebDragSource::OnDragSourceDrop() {
@@ -84,12 +86,23 @@ void WebDragSource::OnDragSourceDrop() {
 void WebDragSource::DelayedOnDragSourceDrop() {
   if (!web_contents_)
     return;
-
   gfx::Point client;
   gfx::Point screen;
   GetCursorPositions(source_wnd_, &client, &screen);
   web_contents_->DragSourceEndedAt(client.x(), client.y(), screen.x(),
                                    screen.y(), WinDragOpToWebDragOp(effect_));
+  OnDragSourceEnded();
+}
+
+void WebDragSource::OnDragSourceEnded() {
+  RenderViewHost* render_view_host = web_contents_->GetRenderViewHost();

[dcheng, 2013/05/24 01:10:37]

Why not just GetRenderWidgetHostView() directly?

[Hongbo Min, 2013/05/27 14:51:41]

Done.

+  if (!render_view_host)
+    return;
+
+  RenderWidgetHostViewWin* rwhv =
+      static_cast<RenderWidgetHostViewWin*>(render_view_host->GetView());
+  if (rwhv->in_long_press_gesture())
+    rwhv->CancelLongPressGesture();
 }
 
 void WebDragSource::OnDragSourceMove() {
@@ -111,6 +124,16 @@ void WebDragSource::OnDragSourceMove() {
                                    screen.x(), screen.y());
 }
 
+bool WebDragSource::ShouldDropDragSource(
+    BOOL escape_pressed, DWORD key_state) {
+  // We also care about right mouse button state since long press gesture is
+  // simulated as right mouse button down/up.
+  LOG(INFO) << "call WebDragSource::ShouldDropDragSource: key_state: "
+            << key_state;
+
+  return !(key_state & MK_LBUTTON) && !(key_state & MK_RBUTTON);

[dcheng, 2013/05/24 01:10:37]

I would prefer to see the right-mouse button check more tightly bound to the
fact that it's due to a touch-initiated drag. In fact, I think we should just
move this logic into DragSourceWin in ui/base/dragdrop. Basically, DragSourceWin
would take an enum in its constructor that indicates whether it's for a touch or
mouse-initiated drag. Then QueryContinueDrag could simply use that to check.

[Hongbo Min, 2013/05/27 14:51:41]

Good suggestion, thanks. Done! 

+}
+
 void WebDragSource::Observe(int type,
                             const NotificationSource& source,
                             const NotificationDetails& details) {