Chrome OS: Fix caption button hover states after snap

Bug: 888613

Change-Id: If7bb4952eb3a19d4d32afec18dc037e66d4c55b4
Reviewed-on: https://chromium-review.googlesource.com/1239363Reviewed-by: James Cook <jamescook@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593682}

ash/public/cpp/caption_buttons/frame_size_button.cc

@@ -100,8 +100,10 @@ bool FrameSizeButton::OnMouseDragged(const ui::MouseEvent& event) {
 }
 
 void FrameSizeButton::OnMouseReleased(const ui::MouseEvent& event) {
-  if (!IsTriggerableEvent(event) || !CommitSnap(event))
-    FrameCaptionButton::OnMouseReleased(event);
+  if (IsTriggerableEvent(event))
+    CommitSnap(event);
+
+  FrameCaptionButton::OnMouseReleased(event);
 }
 
 void FrameSizeButton::OnMouseCaptureLost() {
@@ -210,7 +212,7 @@ void FrameSizeButton::UpdateSnapPreview(const ui::LocatedEvent& event) {
   }
 
   delegate_->SetHoveredAndPressedButtons(to_hover,
-                                         press_size_button ? this : NULL);
+                                         press_size_button ? this : nullptr);
   delegate_->ShowSnapPreview(snap);
 }
 
@@ -232,6 +234,7 @@ bool FrameSizeButton::CommitSnap(const ui::LocatedEvent& event) {
   FrameCaptionDelegate::SnapDirection snap =
       GetSnapDirection(GetButtonToHover(event));
   delegate_->CommitSnap(snap);
+  delegate_->SetHoveredAndPressedButtons(nullptr, nullptr);
 
   if (snap == FrameCaptionDelegate::SnapDirection::kLeft) {
     base::RecordAction(base::UserMetricsAction("MaxButton_MaxLeft"));