Don't preview autofill/autocomplete until first real mouse move.

chrome/browser/ui/views/autofill/autofill_popup_base_view.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 "chrome/browser/ui/views/autofill/autofill_popup_base_view.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/message_loop/message_loop.h"
 #include "chrome/browser/ui/autofill/popup_constants.h"
@@ skipping 125 matching lines @@
   // Pressing return causes the cursor to hide, which will generate an
   // OnMouseExited event. Pressing return should activate the current selection
   // via AcceleratorPressed, so we need to let that run first.
   base::MessageLoop::current()->PostTask(
       FROM_HERE,
       base::Bind(&AutofillPopupBaseView::ClearSelection,
                  weak_ptr_factory_.GetWeakPtr()));
 }
 
 void AutofillPopupBaseView::OnMouseMoved(const ui::MouseEvent& event) {
+  // A synthesized mouse move will be sent when the popup is first shown.
+  // Don't preview a suggestion if the mouse happens to be hovering there.
+  if (event.flags() & ui::EF_IS_SYNTHESIZED)
+    return;
+
   if (HitTestPoint(event.location()))
     SetSelection(event.location());
   else
     ClearSelection();
 }
 
 bool AutofillPopupBaseView::OnMousePressed(const ui::MouseEvent& event) {
   return event.GetClickCount() == 1;
 }
 
@@ skipping 67 matching lines @@
 void AutofillPopupBaseView::HideController() {
   if (delegate_)
     delegate_->Hide();
 }
 
 gfx::NativeView AutofillPopupBaseView::container_view() {
   return delegate_->container_view();
 }
 
 }  // namespace autofill