--- a/dom/html/HTMLInputElement.cpp
+++ b/dom/html/HTMLInputElement.cpp
@@ -4123,16 +4123,27 @@ HTMLInputElement::MaybeInitPickers(Event
   }
   if (mType == NS_FORM_INPUT_DATE) {
     return InitDatePicker();
   }
 
   return NS_OK;
 }
 
+/**
+ * Return true if the input event should be ignore because of it's modifiers
+ */
+static bool
+IgnoreInputEventWithModifier(WidgetInputEvent* aEvent)
+{
+  return aEvent->IsShift() || aEvent->IsControl() || aEvent->IsAlt() ||
+         aEvent->IsMeta() || aEvent->IsAltGraph() || aEvent->IsFn() ||
+         aEvent->IsOS();
+}
+
 nsresult
 HTMLInputElement::PostHandleEvent(EventChainPostVisitor& aVisitor)
 {
   if (!aVisitor.mPresContext) {
     // Hack alert! In order to open file picker even in case the element isn't
     // in document, try to init picker even without PresContext.
     return MaybeInitPickers(aVisitor);
   }
@@ -4269,20 +4280,17 @@ HTMLInputElement::PostHandleEvent(EventC
   }
 
   if (NS_SUCCEEDED(rv)) {
     WidgetKeyboardEvent* keyEvent = aVisitor.mEvent->AsKeyboardEvent();
     if (mType ==  NS_FORM_INPUT_NUMBER &&
         keyEvent && keyEvent->mMessage == eKeyPress &&
         aVisitor.mEvent->IsTrusted() &&
         (keyEvent->mKeyCode == NS_VK_UP || keyEvent->mKeyCode == NS_VK_DOWN) &&
-        !(keyEvent->IsShift() || keyEvent->IsControl() ||
-          keyEvent->IsAlt() || keyEvent->IsMeta() ||
-          keyEvent->IsAltGraph() || keyEvent->IsFn() ||
-          keyEvent->IsOS())) {
+        !IgnoreInputEventWithModifier(keyEvent)) {
       // We handle the up/down arrow keys specially for <input type=number>.
       // On some platforms the editor for the nested text control will
       // process these keys to send the cursor to the start/end of the text
       // control and as a result aVisitor.mEventStatus will already have been
       // set to nsEventStatus_eConsumeNoDefault. However, we know that
       // whenever the up/down arrow keys cause the value of the number
       // control to change the string in the text control will change, and
       // the cursor will be moved to the end of the text control, overwriting
@@ -4491,20 +4499,17 @@ HTMLInputElement::PostHandleEvent(EventC
                 aVisitor.mDOMEvent->StopPropagation();
               } else {
                 rv = NS_ERROR_FAILURE;
               }
             }
           }
           if (mType == NS_FORM_INPUT_NUMBER && aVisitor.mEvent->IsTrusted()) {
             if (mouseEvent->button == WidgetMouseEvent::eLeftButton &&
-                !(mouseEvent->IsShift() || mouseEvent->IsControl() ||
-                  mouseEvent->IsAlt() || mouseEvent->IsMeta() ||
-                  mouseEvent->IsAltGraph() || mouseEvent->IsFn() ||
-                  mouseEvent->IsOS())) {
+                !IgnoreInputEventWithModifier(mouseEvent)) {
               nsNumberControlFrame* numberControlFrame =
                 do_QueryFrame(GetPrimaryFrame());
               if (numberControlFrame) {
                 if (aVisitor.mEvent->mMessage == eMouseDown &&
                     IsMutable()) {
                   switch (numberControlFrame->GetSpinButtonForPointerEvent(
                             aVisitor.mEvent->AsMouseEvent())) {
                   case nsNumberControlFrame::eSpinButtonUp:
@@ -4657,20 +4662,17 @@ HTMLInputElement::PostHandleEventForRang
     case eTouchStart: {
       if (mIsDraggingRange) {
         break;
       }
       if (nsIPresShell::GetCapturingContent()) {
         break; // don't start drag if someone else is already capturing
       }
       WidgetInputEvent* inputEvent = aVisitor.mEvent->AsInputEvent();
-      if (inputEvent->IsShift() || inputEvent->IsControl() ||
-          inputEvent->IsAlt() || inputEvent->IsMeta() ||
-          inputEvent->IsAltGraph() || inputEvent->IsFn() ||
-          inputEvent->IsOS()) {
+      if (IgnoreInputEventWithModifier(inputEvent)) {
         break; // ignore
       }
       if (aVisitor.mEvent->mMessage == eMouseDown) {
         if (aVisitor.mEvent->AsMouseEvent()->buttons ==
               WidgetMouseEvent::eLeftButtonFlag) {
           StartRangeThumbDrag(inputEvent);
         } else if (mIsDraggingRange) {
           CancelRangeThumbDrag();