Remove extraneous call to RemovePreTargetHandler

QuickAnswersView never gets added as a pre-target handler, so call to
RemovePreTargetHandler in ~QuickAnswersView() is extraneous and is thus
removed.

Bug: b:150475423
Test: Tested on Chrome OS VM.
Change-Id: Id1246e27d626daa4a6da5bb32d9b1c471c410c1e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2216531
Commit-Queue: Abhijeet Singh <siabhijeet@google.com>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: David Black <dmblack@google.com>
Cr-Commit-Position: refs/heads/master@{#772440}

ash/quick_answers/ui/quick_answers_view.cc

@@ -137,9 +137,7 @@ QuickAnswersView::QuickAnswersView(const gfx::Rect& anchor_view_bounds,
       reinterpret_cast<void*>(views::MenuConfig::kMenuControllerGroupingId));
 }
 
-QuickAnswersView::~QuickAnswersView() {
-  Shell::Get()->RemovePreTargetHandler(this);
-}
+QuickAnswersView::~QuickAnswersView() = default;
 
 const char* QuickAnswersView::GetClassName() const {
   return "QuickAnswersView";