[CodeHealth] Remove unused ui::Layer::ShouldDraw()

This function is unused.

Bug: None
Change-Id: Ic0c39655a6ea8087dbfbf2150e4d1478163b06e5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1795756Reviewed-by: kylechar <kylechar@chromium.org>
Commit-Queue: Yi Gu <yigu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695263}

ui/compositor/layer.cc

@@ -668,10 +668,6 @@ bool Layer::IsDrawn() const {
   return layer == nullptr;
 }
 
-bool Layer::ShouldDraw() const {
-  return type_ != LAYER_NOT_DRAWN && GetCombinedOpacity() > 0.0f;
-}
-
 void Layer::SetRoundedCornerRadius(const gfx::RoundedCornersF& corner_radii) {
   GetAnimator()->SetRoundedCorners(corner_radii);
 }

ui/compositor/layer.h

@@ -296,10 +296,6 @@ class COMPOSITOR_EXPORT Layer : public LayerAnimationDelegate,
   // are visible.
   bool IsDrawn() const;
 
-  // Returns true if this layer can have a texture (has_texture_ is true)
-  // and is not completely obscured by a child.
-  bool ShouldDraw() const;
-
   // If set to true, this layer can receive hit test events, this property does
   // not affect the layer's descendants.
   void SetAcceptEvents(bool accept_events);