cc: Simplify the logic for deciding to update tile priorities.

cc/trees/layer_tree_host_common.cc

Index: cc/trees/layer_tree_host_common.cc
diff --git a/cc/trees/layer_tree_host_common.cc b/cc/trees/layer_tree_host_common.cc
index 7548cd293bbf1a2212062e961bc269fa34b0f08e..310e17ad7845482fbbacf3799f919ed3f67bdc4a 100644
--- a/cc/trees/layer_tree_host_common.cc
+++ b/cc/trees/layer_tree_host_common.cc
@@ -412,10 +412,10 @@ gfx::Transform ComputeSizeDeltaCompensation(
   // Apply step 3
   gfx::Transform container_layer_space_to_target_surface_space;
   if (target_surface_space_to_container_layer_space.GetInverse(
-      &container_layer_space_to_target_surface_space))
+          &container_layer_space_to_target_surface_space)) {
     result_transform.PreconcatTransform(
         container_layer_space_to_target_surface_space);
-  else {
+  } else {
     // FIXME: A non-invertible matrix could still make meaningful projection.
     // For example ScaleZ(0) is non-invertible but the layer is still visible.
     return gfx::Transform();
@@ -440,8 +440,7 @@ void ApplyPositionAdjustment(
     LayerImpl* layer,
     LayerImpl* container,
     const gfx::Transform& scroll_compensation,
-    gfx::Transform* combined_transform)
-{
+    gfx::Transform* combined_transform) {
   if (!layer->position_constraint().is_fixed_position())
     return;
 
@@ -777,8 +776,7 @@ static void CalculateDrawPropertiesInternal(
     float device_scale_factor,
     float page_scale_factor,
     bool subtree_can_use_lcd_text,
-    gfx::Rect* drawable_content_rect_of_subtree,
-    bool update_tile_priorities) {
+    gfx::Rect* drawable_content_rect_of_subtree) {
   // This function computes the new matrix transformations recursively for this
   // layer and all its descendants. It also computes the appropriate render
   // surfaces.
@@ -1256,8 +1254,7 @@ static void CalculateDrawPropertiesInternal(
         device_scale_factor,
         page_scale_factor,
         subtree_can_use_lcd_text,
-        &drawable_content_rect_of_child_subtree,
-        update_tile_priorities);
+        &drawable_content_rect_of_child_subtree);
     if (!drawable_content_rect_of_child_subtree.IsEmpty()) {
       accumulated_drawable_content_rect_of_children.Union(
           drawable_content_rect_of_child_subtree);
@@ -1391,8 +1388,7 @@ static void CalculateDrawPropertiesInternal(
     }
   }
 
-  if (update_tile_priorities)
-    UpdateTilePrioritiesForLayer(layer);
+  UpdateTilePrioritiesForLayer(layer);
 
   // If neither this layer nor any of its children were added, early out.
   if (sorting_start_index == descendants.size())
@@ -1442,7 +1438,6 @@ void LayerTreeHostCommon::CalculateDrawProperties(
   // initial clip rect.
   bool subtree_should_be_clipped = true;
   gfx::Rect device_viewport_rect(device_viewport_size);
-  bool update_tile_priorities = false;
 
   // This function should have received a root layer.
   DCHECK(IsRootLayer(root_layer));
@@ -1466,8 +1461,7 @@ void LayerTreeHostCommon::CalculateDrawProperties(
                                                  device_scale_factor,
                                                  page_scale_factor,
                                                  can_use_lcd_text,
-                                                 &total_drawable_content_rect,
-                                                 update_tile_priorities);
+                                                 &total_drawable_content_rect);
 
   // The dummy layer list should not have been used.
   DCHECK_EQ(0u, dummy_layer_list.size());
@@ -1483,8 +1477,7 @@ void LayerTreeHostCommon::CalculateDrawProperties(
     float page_scale_factor,
     int max_texture_size,
     bool can_use_lcd_text,
-    LayerImplList* render_surface_layer_list,
-    bool update_tile_priorities) {
+    LayerImplList* render_surface_layer_list) {
   gfx::Rect total_drawable_content_rect;
   gfx::Transform identity_matrix;
   gfx::Transform device_scale_transform;
@@ -1520,8 +1513,7 @@ void LayerTreeHostCommon::CalculateDrawProperties(
       device_scale_factor,
       page_scale_factor,
       can_use_lcd_text,
-      &total_drawable_content_rect,
-      update_tile_priorities);
+      &total_drawable_content_rect);
 
   // The dummy layer list should not have been used.
   DCHECK_EQ(0u, dummy_layer_list.size());