Ensure that mouse events on Windows reposted by the menu_controller are converted to pixel.

ui/views/controls/menu/menu_controller.cc

Index: ui/views/controls/menu/menu_controller.cc
diff --git a/ui/views/controls/menu/menu_controller.cc b/ui/views/controls/menu/menu_controller.cc
index 87e7ad2ab088321e93ec1edbbb41730936419c88..7d07345b40ff1bf98847c855c52e19feafa87081 100644
--- a/ui/views/controls/menu/menu_controller.cc
+++ b/ui/views/controls/menu/menu_controller.cc
@@ -39,6 +39,7 @@
 
 #if defined(OS_WIN)
 #include "ui/base/win/internal_constants.h"
+#include "ui/gfx/win/dpi.h"
 #include "ui/views/win/hwnd_util.h"
 #endif
 
@@ -89,6 +90,26 @@ bool TitleMatchesMnemonic(MenuItemView* menu, base::char16 key) {
   return !lower_title.empty() && lower_title[0] == key;
 }
 
+// Returns the window and the screen location for the coordinates identified
+// by |event|. The window is returned in the output parameter |window| and
+// the screen location is returned in the output parameter |screen_location|.
+void PlatformGetWindowAtLocation(const ui::LocatedEvent& event,
+                                 SubmenuView* source,
+                                 gfx::NativeView native_view,
+                                 gfx::NativeWindow* window,
+                                 gfx::Point* screen_location) {
+  gfx::Point screen_loc(event.location());
+  View::ConvertPointToScreen(source->GetScrollViewContainer(), &screen_loc);
+  gfx::Screen* screen = gfx::Screen::GetScreenFor(native_view);
+#if defined(OS_WIN)
+  // On Windows convert the coordinates from DIP to pixel to ensure that we
+  // get the correct window.
+  screen_loc = gfx::win::DIPToScreenPoint(screen_loc);
+#endif
+  *window = screen->GetWindowAtScreenPoint(screen_loc);

[sky, 2014/06/18 22:20:26]

Something seems wrong here. Why does GetWindowAtScreenPoint want pixel points?
It seems wrong that ConvertPointToScreen returns DIPs yet screen functions want
pixels. Is that right?

[oshima, 2014/06/18 22:27:51]

Yes, both must be in DIP.

[ananta, 2014/06/18 22:57:10]

I updated the patch to fix ScreenWin::GetWindowAtScreenPoint to convert to
pixels
before calling WindowFromPoint. The other change is in menu_controller.cc to
convert screen_loc to pixels in the #if defined(OS_WIN) block in RepostEvent.
Added comments as to why that is needed.

PTAL.

+  *screen_location = screen_loc;
+}
+
 }  // namespace
 
 // Returns the first descendant of |view| that is hot tracked.
@@ -2042,15 +2063,15 @@ void MenuController::RepostEvent(SubmenuView* source,
   state_.item->GetRootMenuItem()->GetSubmenu()->ReleaseCapture();
 #endif
 
-  gfx::Point screen_loc(event.location());
-  View::ConvertPointToScreen(source->GetScrollViewContainer(), &screen_loc);
   gfx::NativeView native_view = source->GetWidget()->GetNativeView();
   if (!native_view)
     return;
 
-  gfx::Screen* screen = gfx::Screen::GetScreenFor(native_view);
-  gfx::NativeWindow window = screen->GetWindowAtScreenPoint(screen_loc);
+  gfx::NativeWindow window = NULL;
+  gfx::Point screen_loc;
 
+  PlatformGetWindowAtLocation(event, source, native_view, &window,
+                              &screen_loc);
 #if defined(OS_WIN)
   // PostMessage() to metro windows isn't allowed (access will be denied). Don't
   // try to repost with Win32 if the window under the mouse press is in metro.
@@ -2068,7 +2089,6 @@ void MenuController::RepostEvent(SubmenuView* source,
       // else double events can occur and lead to bad behavior.
       return;
     }
-
     // Determine whether the click was in the client area or not.
     // NOTE: WM_NCHITTEST coordinates are relative to the screen.
     LPARAM coords = MAKELPARAM(screen_loc.x(), screen_loc.y());