Update from chromium https://crrev.com/302282

cc/output/overlay_strategy_single_on_top.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 "cc/output/overlay_strategy_single_on_top.h"
 
 #include "cc/quads/draw_quad.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/transform.h"
@@ skipping 12 matching lines @@
   // Only attempt to handle very simple case for now.
   if (!capability_checker_)
     return false;
 
   RenderPass* root_render_pass = render_passes_in_draw_order->back();
   DCHECK(root_render_pass);
 
   QuadList& quad_list = root_render_pass->quad_list;
   auto candidate_iterator = quad_list.end();
   for (auto it = quad_list.begin(); it != quad_list.end(); ++it) {
-    const DrawQuad* draw_quad = &*it;
+    const DrawQuad* draw_quad = *it;
     if (draw_quad->material == DrawQuad::TEXTURE_CONTENT) {
       const TextureDrawQuad& quad = *TextureDrawQuad::MaterialCast(draw_quad);
       if (!resource_provider_->AllowOverlay(quad.resource_id)) {
         continue;
       }
       // Check that no prior quads overlap it.
       bool intersects = false;
       gfx::RectF rect = draw_quad->rect;
       draw_quad->quadTransform().TransformRect(&rect);
       for (auto overlap_iter = quad_list.cbegin(); overlap_iter != it;
            ++overlap_iter) {
         gfx::RectF overlap_rect = overlap_iter->rect;
         overlap_iter->quadTransform().TransformRect(&overlap_rect);
         if (rect.Intersects(overlap_rect)) {
           intersects = true;
           break;
         }
       }
       if (intersects)
         continue;
       candidate_iterator = it;
       break;
     }
   }
   if (candidate_iterator == quad_list.end())
     return false;
   const TextureDrawQuad& quad =
-      *TextureDrawQuad::MaterialCast(&*candidate_iterator);
+      *TextureDrawQuad::MaterialCast(*candidate_iterator);
 
   // Simple quads only.
   gfx::OverlayTransform overlay_transform =
       OverlayCandidate::GetOverlayTransform(quad.quadTransform(), quad.flipped);
   if (overlay_transform == gfx::OVERLAY_TRANSFORM_INVALID ||
       !quad.quadTransform().IsIdentityOrTranslation() || quad.needs_blending ||
       quad.shared_quad_state->opacity != 1.f ||
       quad.shared_quad_state->blend_mode != SkXfermode::kSrcOver_Mode ||
       quad.premultiplied_alpha || quad.background_color != SK_ColorTRANSPARENT)
     return false;
@@ skipping 22 matching lines @@
   // If the candidate can be handled by an overlay, create a pass for it.
   if (candidates[1].overlay_handled) {
     quad_list.EraseAndInvalidateAllPointers(candidate_iterator);
     candidate_list->swap(candidates);
     return true;
   }
   return false;
 }
 
 }  // namespace cc