Fix grabbing capture when the mouse is pressed on Desktop Linux.

ui/views/widget/desktop_aura/desktop_drag_drop_client_aurax11_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <map>
 #include <vector>
 
 // Include views_test_base.h first because the definition of None in X.h
 // conflicts with the definition of None in gtest-type-util.h
 #include "ui/views/test/views_test_base.h"
@@ skipping 68 matching lines @@
 // loop.
 class TestMoveLoop : public X11MoveLoop {
  public:
   explicit TestMoveLoop(X11MoveLoopDelegate* delegate);
   ~TestMoveLoop() override;
 
   // Returns true if the move loop is running.
   bool IsRunning() const;
 
   // X11MoveLoop:
-  bool RunMoveLoop(aura::Window* window, gfx::NativeCursor cursor) override;
+  bool RunMoveLoop(aura::Window* window) override;
   void UpdateCursor(gfx::NativeCursor cursor) override;
   void EndMoveLoop() override;
 
  private:
   // Not owned.
   X11MoveLoopDelegate* delegate_;
 
   // Ends the move loop.
   base::Closure quit_closure_;
 
@@ skipping 109 matching lines @@
       is_running_(false) {
 }
 
 TestMoveLoop::~TestMoveLoop() {
 }
 
 bool TestMoveLoop::IsRunning() const {
   return is_running_;
 }
 
-bool TestMoveLoop::RunMoveLoop(
-    aura::Window* window,
-    gfx::NativeCursor cursor) {
+bool TestMoveLoop::RunMoveLoop(aura::Window* window) {
   is_running_ = true;
   base::RunLoop run_loop;
   quit_closure_ = run_loop.QuitClosure();
   run_loop.Run();
   return true;
 }
 
 void TestMoveLoop::UpdateCursor(gfx::NativeCursor cursor) {
 }
 
@@ skipping 482 matching lines @@
 
   // Repeat the test but reject the drop in the XdndFinished message instead.
   base::MessageLoop::current()->PostTask(
       FROM_HERE,
       base::Bind(&RejectAfterMouseReleaseStep3, client()));
   result = StartDragAndDrop();
   EXPECT_EQ(ui::DragDropTypes::DRAG_NONE, result);
 }
 
 }  // namespace views