Desktop Aura: Allow tab drags out of window.

ui/base/win/events_win.cc

Index: ui/base/win/events_win.cc
diff --git a/ui/base/win/events_win.cc b/ui/base/win/events_win.cc
index 984e7ca3d6736cfcce595600657cca9762332872..5cf937c5a7322f5ccb791a5add563e7d7a63ebf0 100644
--- a/ui/base/win/events_win.cc
+++ b/ui/base/win/events_win.cc
@@ -215,6 +215,13 @@ gfx::Point EventLocationFromNative(const base::NativeEvent& native_event) {
   return gfx::Point(native_point);
 }
 
+gfx::Point EventSystemLocationFromNative(
+    const base::NativeEvent& native_event) {
+  // TODO(ben): Needs to always return screen position here. Returning normal
+  // origin for now since that's obviously wrong.
+  return gfx::Point(0, 0);
+}
+
 KeyboardCode KeyboardCodeFromNative(const base::NativeEvent& native_event) {
   return KeyboardCodeForWindowsKeyCode(native_event.wParam);
 }