Fixed drag and drop into and out of Browser Plugin.

content/browser/browser_plugin/browser_plugin_guest.cc

Index: content/browser/browser_plugin/browser_plugin_guest.cc
diff --git a/content/browser/browser_plugin/browser_plugin_guest.cc b/content/browser/browser_plugin/browser_plugin_guest.cc
index 973408fbd476f1fa1a1d651c24368d9a7ca8a06c..17335bfb77048f46fac0c3b75f8a331b113a76d0 100644
--- a/content/browser/browser_plugin/browser_plugin_guest.cc
+++ b/content/browser/browser_plugin/browser_plugin_guest.cc
@@ -6,6 +6,7 @@
 
 #include <algorithm>
 
+#include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
@@ -34,6 +35,7 @@
 #include "content/public/browser/resource_request_details.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents_view.h"
+#include "content/public/common/content_switches.h"
 #include "content/public/common/media_stream_request.h"
 #include "content/public/common/result_codes.h"
 #include "net/base/net_errors.h"
@@ -485,6 +487,22 @@ void BrowserPluginGuest::SendMessageToEmbedder(IPC::Message* msg) {
   embedder_web_contents_->Send(msg);
 }
 
+void BrowserPluginGuest::DragSourceEndedAt(int client_x, int client_y,
+    int screen_x, int screen_y, WebKit::WebDragOperation operation) {
+  web_contents()->GetRenderViewHost()->DragSourceEndedAt(client_x, client_y,
+      screen_x, screen_y, operation);
+}
+
+void BrowserPluginGuest::DragSourceMovedTo(int client_x, int client_y,
+                                           int screen_x, int screen_y) {
+  web_contents()->GetRenderViewHost()->DragSourceMovedTo(client_x, client_y,
+                                                         screen_x, screen_y);
+}
+
+void BrowserPluginGuest::EndSystemDrag() {
+  web_contents()->GetRenderViewHost()->DragSourceSystemDragEnded();

[Fady Samuel, 2013/04/09 20:49:12]

This ought to fix the sticky selection problem:

void BrowserPluginGuest::EndSystemDrag() {
  RenderViewHostImpl* guest_rvh = static_cast<RenderViewHostImpl*>(
      GetWebContents()->GetRenderViewHost());
  guest_rvh->DragSourceSystemDragEnded();
  // Issue a MouseUp event to get out of a selection state.
  WebKit::WebMouseEvent mouse_event;
  mouse_event.type = WebKit::WebInputEvent::MouseUp;
  mouse_event.button = WebKit::WebMouseEvent::ButtonLeft;
  guest_rvh->ForwardMouseEvent(mouse_event);
}

[mthiesse, 2013/04/18 18:02:03]

Done. Thanks.

+}
+
 void BrowserPluginGuest::LoadRedirect(
     const GURL& old_url,
     const GURL& new_url,
@@ -557,13 +575,22 @@ void BrowserPluginGuest::DidCommitProvisionalLoadForFrame(
 }
 
 void BrowserPluginGuest::DidStopLoading(RenderViewHost* render_view_host) {
-  // Initiating a drag from inside a guest is currently not supported. So inject
-  // some JS to disable it. http://crbug.com/161112
-  const char script[] = "window.addEventListener('dragstart', function() { "
-                        "  window.event.preventDefault(); "
-                        "});";
-  render_view_host->ExecuteJavascriptInWebFrame(string16(),
-                                                ASCIIToUTF16(script));
+  bool disable_dragdrop = true;
+#if (defined(OS_LINUX))
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+        switches::kEnableBrowserPluginDragDrop))
+    disable_dragdrop = false;
+#endif  // (defined(OS_LINUX))
+  if (disable_dragdrop) {
+    // Initiating a drag from inside a guest is currently not supported without
+    // the kEnableBrowserPluginGuestViews flag. So inject some JS to disable

[Fady Samuel, 2013/04/09 20:49:12]

Stale comment.

[mthiesse, 2013/04/18 18:02:03]

Done.

+    // it. http://crbug.com/161112
+    const char script[] = "window.addEventListener('dragstart', function() { "
+                          "  window.event.preventDefault(); "
+                          "});";
+    render_view_host->ExecuteJavascriptInWebFrame(string16(),
+                                                  ASCIIToUTF16(script));
+  }
   SendMessageToEmbedder(new BrowserPluginMsg_LoadStop(instance_id()));
 }
 
@@ -661,9 +688,12 @@ bool BrowserPluginGuest::OnMessageReceived(const IPC::Message& message) {
  #endif
     IPC_MESSAGE_HANDLER(ViewHostMsg_ShowView, OnShowView)
     IPC_MESSAGE_HANDLER(ViewHostMsg_ShowWidget, OnShowWidget)
+    IPC_MESSAGE_HANDLER_GENERIC(DragHostMsg_StartDragging,
+                                OnStartDragging(&handled));
     IPC_MESSAGE_HANDLER(ViewHostMsg_TakeFocus, OnTakeFocus)
+    IPC_MESSAGE_HANDLER_GENERIC(DragHostMsg_TargetDrop_ACK,
+                                OnTargetDrop_ACK(&handled));
     IPC_MESSAGE_HANDLER(ViewHostMsg_UnlockMouse, OnUnlockMouse)
-    IPC_MESSAGE_HANDLER(DragHostMsg_UpdateDragCursor, OnUpdateDragCursor)
     IPC_MESSAGE_HANDLER(ViewHostMsg_UpdateFrameName, OnUpdateFrameName)
     IPC_MESSAGE_HANDLER(ViewHostMsg_UpdateRect, OnUpdateRect)
     IPC_MESSAGE_UNHANDLED(handled = false)
@@ -728,16 +758,20 @@ void BrowserPluginGuest::OnDragStatusUpdate(int instance_id,
   RenderViewHost* host = GetWebContents()->GetRenderViewHost();
   switch (drag_status) {
     case WebKit::WebDragStatusEnter:
+      embedder_web_contents_->GetBrowserPluginEmbedder()->DragEnteredGuest(
+          this);
       host->DragTargetDragEnter(drop_data, location, location, mask, 0);
       break;
     case WebKit::WebDragStatusOver:
       host->DragTargetDragOver(location, location, mask, 0);
       break;
     case WebKit::WebDragStatusLeave:
+      embedder_web_contents_->GetBrowserPluginEmbedder()->DragLeftGuest(this);
       host->DragTargetDragLeave();
       break;
     case WebKit::WebDragStatusDrop:
       host->DragTargetDrop(location, location, 0);
+      host->DragSourceSystemDragEnded();

[Fady Samuel, 2013/04/09 20:49:12]

EndSystemDrag();

[mthiesse, 2013/04/18 18:02:03]

Done.

       break;
     case WebKit::WebDragStatusUnknown:
       NOTREACHED();
@@ -1051,21 +1085,23 @@ void BrowserPluginGuest::OnShowWidget(int route_id,
   GetWebContents()->ShowCreatedWidget(route_id, screen_pos);
 }
 
+void BrowserPluginGuest::OnStartDragging(bool* handled) {
+  embedder_web_contents_->GetBrowserPluginEmbedder()->StartDrag(this);

[Fady Samuel, 2013/04/09 20:49:12]

Why not just move this to WebContentsViewGuest::StartDragging  to avoid this
method all together?

[mthiesse, 2013/04/18 18:02:03]

Done.

+  // Don't mark as handled, so that the message gets routed to
+  // RenderViewHostImpl::OnStartDragging, which in turn calls
+  // WebContentsViewGuest::StartDragging, which starts the drag on the embedder.
+  *handled = false;
+}
+
 void BrowserPluginGuest::OnTakeFocus(bool reverse) {
   SendMessageToEmbedder(
       new BrowserPluginMsg_AdvanceFocus(instance_id(), reverse));
 }
 
-void BrowserPluginGuest::OnUpdateDragCursor(
-    WebKit::WebDragOperation operation) {
-  RenderViewHostImpl* embedder_render_view_host =
-      static_cast<RenderViewHostImpl*>(
-          embedder_web_contents_->GetRenderViewHost());
-  CHECK(embedder_render_view_host);
-  RenderViewHostDelegateView* view =
-      embedder_render_view_host->GetDelegate()->GetDelegateView();
-  if (view)
-    view->UpdateDragCursor(operation);
+void BrowserPluginGuest::OnTargetDrop_ACK(bool* handled) {
+  EndSystemDrag();
+  // Don't mark as handled.

[Fady Samuel, 2013/04/09 20:49:12]

This comment on its own is not very useful. Please explain why we do this?

Actually it seems like we either need to call EndSystemDrag() here or
host->DragSourceSystemDragEnded(); in BrowserPluginGuest::OnDragStatusUpdate?

Do we need both? If not, maybe we simply get rid of this one and leave the
other? I'm not sure.

[mthiesse, 2013/04/18 18:02:03]

Ah, meant to clean this up, was part of my experiments to fix drag and drop on
windows.

+  *handled = false;
 }
 
 void BrowserPluginGuest::OnUpdateFrameName(int frame_id,