Revert of cc: Remove tile rasterize on demand for GPU rasterization

cc/resources/tile_manager.cc

Index: cc/resources/tile_manager.cc
diff --git a/cc/resources/tile_manager.cc b/cc/resources/tile_manager.cc
index a6693529fc1dda2fedf6e4e4fe38bd0f09af97bd..dff3a52f871ac6a80cd05b77e92fc25ab6b14fed 100644
--- a/cc/resources/tile_manager.cc
+++ b/cc/resources/tile_manager.cc
@@ -418,6 +418,28 @@
       tiles_that_need_to_be_rasterized, resource_pool_,
       base::Bind(&TileManager::UpdateTileDrawInfo, base::Unretained(this)));
 
+  // Use on-demand raster for any required-for-activation tiles that have not
+  // been been assigned memory after reaching a steady memory state. This
+  // ensures that we activate even when OOM. Note that we have to rebuilt the
+  // queue in case the last AssignGpuMemoryToTiles evicted some tiles that would
+  // otherwise not be picked up by the old raster queue.
+  client_->BuildRasterQueue(&raster_priority_queue_,
+                            global_state_.tree_priority);
+
+  // Use on-demand raster for any tiles that have not been been assigned
+  // memory. This ensures that we draw even when OOM.
+  while (!raster_priority_queue_.IsEmpty()) {
+    Tile* tile = raster_priority_queue_.Top();
+    TileDrawInfo& draw_info = tile->draw_info();
+
+    if (tile->required_for_draw() && !draw_info.IsReadyToDraw()) {
+      draw_info.set_rasterize_on_demand();
+      client_->NotifyTileStateChanged(tile);
+    }
+    raster_priority_queue_.Pop();
+  }
+  raster_priority_queue_.Reset();
+
   TRACE_EVENT_INSTANT1("cc", "DidRasterize", TRACE_EVENT_SCOPE_THREAD, "state",
                        BasicStateAsValue());