Update from https://crrev.com/303153

cc/layers/picture_layer_impl.cc

 // Copyright 2012 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/layers/picture_layer_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <set>
 
@@ skipping 155 matching lines @@
   if (could_have_tilings != CanHaveTilings()) {
     layer_tree_impl()->set_needs_update_draw_properties();
   }
 }
 
 void PictureLayerImpl::AppendQuads(RenderPass* render_pass,
                                    const Occlusion& occlusion_in_content_space,
                                    AppendQuadsData* append_quads_data) {
   DCHECK(!needs_post_commit_initialization_);
   // The bounds and the pile size may differ if the pile wasn't updated (ie.
-  // PictureLayer::Update didn't happen). But that should never be the case if
-  // the layer is part of the visible frame, which is why we're appending quads
-  // in the first place
-  DCHECK_EQ(bounds().ToString(), pile_->tiling_size().ToString());
+  // PictureLayer::Update didn't happen). In that case the pile will be empty.
+  DCHECK_IMPLIES(!pile_->tiling_size().IsEmpty(),
+                 bounds() == pile_->tiling_size())
+      << " bounds " << bounds().ToString() << " pile "
+      << pile_->tiling_size().ToString();
 
   SharedQuadState* shared_quad_state =
       render_pass->CreateAndAppendSharedQuadState();
 
   if (pile_->is_solid_color()) {
     PopulateSharedQuadState(shared_quad_state);
 
     AppendDebugBorderQuad(
         render_pass, bounds(), shared_quad_state, append_quads_data);
 
@@ skipping 271 matching lines @@
 
   // Aggressively remove any tilings that are not seen to save memory. Note
   // that this is at the expense of doing cause more frequent re-painting. A
   // better scheme would be to maintain a tighter visible_content_rect for the
   // finer tilings.
   CleanUpTilingsOnActiveLayer(seen_tilings);
 }
 
 void PictureLayerImpl::UpdateTiles(const Occlusion& occlusion_in_content_space,
                                    bool resourceless_software_draw) {
-  TRACE_EVENT0("cc", "PictureLayerImpl::UpdateTiles");
   DCHECK_EQ(1.f, contents_scale_x());
   DCHECK_EQ(1.f, contents_scale_y());
 
   DoPostCommitInitializationIfNeeded();
 
   if (!resourceless_software_draw) {
     visible_rect_for_tile_priority_ = visible_content_rect();
   }
 
   if (!CanHaveTilings()) {
@@ skipping 27 matching lines @@
     pile_->set_likely_to_be_used_for_transform_animation();
 
   should_update_tile_priorities_ = true;
 
   UpdateTilePriorities(occlusion_in_content_space);
 }
 
 void PictureLayerImpl::UpdateTilePriorities(
     const Occlusion& occlusion_in_content_space) {
   DCHECK(!pile_->is_solid_color() || !tilings_->num_tilings());
-
-  TRACE_EVENT0("cc", "PictureLayerImpl::UpdateTilePriorities");
-
   double current_frame_time_in_seconds =
       (layer_tree_impl()->CurrentBeginFrameArgs().frame_time -
        base::TimeTicks()).InSecondsF();
 
   gfx::Rect viewport_rect_in_layer_space =
       GetViewportForTilePriorityInContentSpace();
   bool tiling_needs_update = false;
   for (size_t i = 0; i < tilings_->num_tilings(); ++i) {
     if (tilings_->tiling_at(i)->NeedsUpdateForFrameAtTimeAndViewport(
             current_frame_time_in_seconds, viewport_rect_in_layer_space)) {
@@ skipping 251 matching lines @@
     tile_height = std::min(tile_height, default_tile_height);
   }
 
   // Under no circumstance should we be larger than the max texture size.
   tile_width = std::min(tile_width, max_texture_size);
   tile_height = std::min(tile_height, max_texture_size);
   return gfx::Size(tile_width, tile_height);
 }
 
 void PictureLayerImpl::SyncFromActiveLayer(const PictureLayerImpl* other) {
-  TRACE_EVENT0("cc", "SyncFromActiveLayer");
   DCHECK(!other->needs_post_commit_initialization_);
   DCHECK(other->tilings_);
 
   if (!DrawsContent()) {
     RemoveAllTilings();
     return;
   }
 
   raster_page_scale_ = other->raster_page_scale_;
   raster_device_scale_ = other->raster_device_scale_;
@@ skipping 276 matching lines @@
     // - When zooming in, approximate ideal using multiple of kMaxScaleRatio.
     bool zooming_out = old_raster_page_scale > ideal_page_scale_;
     float desired_contents_scale =
         zooming_out ? old_raster_contents_scale / kMaxScaleRatioDuringPinch
                     : old_raster_contents_scale * kMaxScaleRatioDuringPinch;
     raster_contents_scale_ = SnappedContentsScale(desired_contents_scale);
     raster_page_scale_ =
         raster_contents_scale_ / raster_device_scale_ / raster_source_scale_;
   }
 
-  raster_contents_scale_ =
-      std::max(raster_contents_scale_, MinimumContentsScale());
-
   // If we're not re-rasterizing during animation, rasterize at the maximum
   // scale that will occur during the animation, if the maximum scale is
   // known. However we want to avoid excessive memory use. If the scale is
   // smaller than what we would choose otherwise, then it's always better off
   // for us memory-wise. But otherwise, we don't choose a scale at which this
   // layer's rastered content would become larger than the viewport.
   if (draw_properties().screen_space_transform_is_animating &&
       !ShouldAdjustRasterScaleDuringScaleAnimations()) {
     bool can_raster_at_maximum_scale = false;
     // TODO(ajuma): If we need to deal with scale-down animations starting right
@@ skipping 11 matching lines @@
     }
     // Use the computed scales for the raster scale directly, do not try to use
     // the ideal scale here. The current ideal scale may be way too large in the
     // case of an animation with scale, and will be constantly changing.
     if (can_raster_at_maximum_scale)
       raster_contents_scale_ = maximum_scale;
     else
       raster_contents_scale_ = 1.f * ideal_page_scale_ * ideal_device_scale_;
   }
 
+  raster_contents_scale_ =
+      std::max(raster_contents_scale_, MinimumContentsScale());
+
   // If this layer would create zero or one tiles at this content scale,
   // don't create a low res tiling.
   gfx::Size raster_bounds = gfx::ToCeiledSize(
       gfx::ScaleSize(pile_->tiling_size(), raster_contents_scale_));
   gfx::Size tile_size = CalculateTileSize(raster_bounds);
   bool tile_covers_bounds = tile_size.width() >= raster_bounds.width() &&
                             tile_size.height() >= raster_bounds.height();
   if (tile_size.IsEmpty() || tile_covers_bounds) {
     low_res_raster_contents_scale_ = raster_contents_scale_;
     return;
   }
 
   float low_res_factor =
       layer_tree_impl()->settings().low_res_contents_scale_factor;
   low_res_raster_contents_scale_ = std::max(
       raster_contents_scale_ * low_res_factor,
       MinimumContentsScale());
+  DCHECK_LE(low_res_raster_contents_scale_, raster_contents_scale_);
+  DCHECK_GE(low_res_raster_contents_scale_, MinimumContentsScale());
 }
 
 void PictureLayerImpl::CleanUpTilingsOnActiveLayer(
     std::vector<PictureLayerTiling*> used_tilings) {
   DCHECK(layer_tree_impl()->IsActiveTree());
   if (tilings_->num_tilings() == 0)
     return;
 
   float min_acceptable_high_res_scale = std::min(
       raster_contents_scale_, ideal_contents_scale_);
@@ skipping 248 matching lines @@
 
 bool PictureLayerImpl::IsOnActiveOrPendingTree() const {
   return !layer_tree_impl()->IsRecycleTree();
 }
 
 bool PictureLayerImpl::HasValidTilePriorities() const {
   return IsOnActiveOrPendingTree() && IsDrawnRenderSurfaceLayerListMember();
 }
 
 bool PictureLayerImpl::AllTilesRequiredForActivationAreReadyToDraw() const {
-  TRACE_EVENT0("cc",
-               "PictureLayerImpl::AllTilesRequiredForActivationAreReadyToDraw");
   if (!layer_tree_impl()->IsPendingTree())
     return true;
 
   if (!HasValidTilePriorities())
     return true;
 
   if (!tilings_)
     return true;
 
   if (visible_rect_for_tile_priority_.IsEmpty())
@@ skipping 301 matching lines @@
       PictureLayerTilingSet::TilingRange tiling_range = CurrentTilingRange();
       size_t current_tiling_range_offset = current_tiling_ - tiling_range.start;
       return tiling_range.end - 1 - current_tiling_range_offset;
     }
   }
   NOTREACHED();
   return 0;
 }
 
 }  // namespace cc