Fixed drag and drop into and out of Browser Plugin.

content/browser/browser_plugin/browser_plugin_embedder.cc

Index: content/browser/browser_plugin/browser_plugin_embedder.cc
diff --git a/content/browser/browser_plugin/browser_plugin_embedder.cc b/content/browser/browser_plugin/browser_plugin_embedder.cc
index 4ffaa3d7b383bdb45bb84d562e2a17ae8b070f4e..5f2cc7820f33c910d16a13319f84b6d3b4b9edb0 100644
--- a/content/browser/browser_plugin/browser_plugin_embedder.cc
+++ b/content/browser/browser_plugin/browser_plugin_embedder.cc
@@ -11,6 +11,7 @@
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/browser_plugin_messages.h"
+#include "content/common/drag_messages.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_service.h"
@@ -195,6 +196,29 @@ BrowserPluginGuest* BrowserPluginEmbedder::GetGuestByInstanceID(
   return NULL;
 }
 
+BrowserPluginGuest* BrowserPluginEmbedder::GetDraggingGuest() const {
+  ContainerInstanceMap::const_iterator it =
+      guest_web_contents_by_instance_id_.begin();
+  for (; it != guest_web_contents_by_instance_id_.end(); ++it) {
+    if (static_cast<WebContentsImpl*>(
+        it->second)->GetBrowserPluginGuest()->dragging())

[Fady Samuel, 2013/02/01 15:54:55]

If we're effectively only allowing one guest to be dragging/dragged over at any
one time, why is the state stored in BrowserPluginGuest and not
BrowserPluginEmbedder?

[mthiesse1, 2013/02/01 16:02:58]

We need a way to identify which guest is the one that's dragging/being dragged
over, and the embedder doesn't know this based on the messages it receives. The
DragHost messages don't include instance IDs.

[mthiesse, 2013/02/01 16:53:44]

Done.

+      return static_cast<WebContentsImpl*>(
+          it->second)->GetBrowserPluginGuest();
+  }
+  return NULL;
+}
+
+bool BrowserPluginEmbedder::IsDragOverGuest() const {
+  ContainerInstanceMap::const_iterator it =
+      guest_web_contents_by_instance_id_.begin();
+  for (; it != guest_web_contents_by_instance_id_.end(); ++it) {
+    if (static_cast<WebContentsImpl*>(
+        it->second)->GetBrowserPluginGuest()->drag_over())
+      return true;
+  }
+  return false;
+}
+
 void BrowserPluginEmbedder::DestroyGuestByInstanceID(int instance_id) {
   BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
   if (guest) {
@@ -228,6 +252,18 @@ void BrowserPluginEmbedder::RenderViewGone(base::TerminationStatus status) {
 }
 
 bool BrowserPluginEmbedder::OnMessageReceived(const IPC::Message& message) {
+  if (message.type() == DragHostMsg_DragStopped::ID) {
+    BrowserPluginGuest* guest = GetDraggingGuest();
+    if (guest)
+      return guest->OnMessageReceived(message);
+  }
+  if (message.type() == DragHostMsg_UpdateDragCursor::ID){
+    // If the guest is being dragged over we want to mark this as handled so
+    // that we don't update the cursor twice, once by the guest, and once by the
+    // embedder (and have the cursor flicker between droppable and
+    // non-droppable).
+    return IsDragOverGuest();
+  }
   if (ShouldForwardToBrowserPluginGuest(message)) {
     int instance_id = 0;
     // All allowed messages must have instance_id as their first parameter.