cc: Separate tiling set functionality into explicit separate functions.

cc/layers/picture_layer_impl.cc

Index: cc/layers/picture_layer_impl.cc
diff --git a/cc/layers/picture_layer_impl.cc b/cc/layers/picture_layer_impl.cc
index e60d425f6c9d2bd554a605701f00bf3ea6060e11..ca85339b3abecc290708db963bf16ad0769b411b 100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -538,12 +538,18 @@ void PictureLayerImpl::UpdateRasterSource(
     return;
   }
 
+  tilings_->RemoveTilingsBelowScale(MinimumContentsScale());

[enne (OOO), 2015/03/31 19:53:02]

I'm not 100% on moving this.  I agree that something called "UpdateRasterSource"
maybe shouldn't be removing tilings, but it really is all about adding tilings
from the pending set if needed, and so removing tilings that aren't needed also
seems like a legit operation to have there too.

What if the RemoveTilings code went into
UpdateTilingsToCurrentRasterSourceForCommit?

[vmpstr, 2015/04/01 23:53:41]

I moved back into both functions (as it would have been before). It makes sense
that since we're creating tilings in that function that we would be removing
them as well. I did add it to both, since I don't want to change behavior with
this patch, just restructure the calls a bit.

+  tilings_->RemoveTilingsAboveScale(MaximumContentsScale());
   // We could do this after doing UpdateTiles, which would avoid doing this for
   // tilings that are going to disappear on the pending tree (if scale changed).
   // But that would also be more complicated, so we just do it here for now.
-  tilings_->UpdateTilingsToCurrentRasterSource(
-      raster_source_, pending_set, invalidation_, MinimumContentsScale(),
-      MaximumContentsScale());
+  if (pending_set) {
+    tilings_->UpdateTilingsToCurrentRasterSourceForActivation(
+        raster_source_, pending_set, invalidation_);
+  } else {
+    tilings_->UpdateTilingsToCurrentRasterSourceForCommit(raster_source_,
+                                                          invalidation_);
+  }
 }
 
 void PictureLayerImpl::UpdateCanUseLCDTextAfterCommit() {
@@ -562,10 +568,12 @@ void PictureLayerImpl::UpdateCanUseLCDTextAfterCommit() {
   // a new one must be created and all tiles recreated.
   scoped_refptr<RasterSource> new_raster_source =
       raster_source_->CreateCloneWithoutLCDText();
+  raster_source_.swap(new_raster_source);
+
   // Synthetically invalidate everything.
   gfx::Rect bounds_rect(bounds());
-  Region invalidation(bounds_rect);
-  UpdateRasterSource(new_raster_source, &invalidation, nullptr);
+  invalidation_ = Region(bounds_rect);
+  tilings_->UpdateRasterSourceDueToLCDChange(raster_source_, invalidation_);
   SetUpdateRect(bounds_rect);
 
   DCHECK(!RasterSourceUsesLCDText());