cc: disable pre-painting when using gpu rasterization.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index fbc4a820f982496949dce7d3040f3a0518f703c4..e647298034b94177c88aedaf8d3e8fd4ba57c395 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -1647,7 +1647,12 @@ void LayerTreeHostImpl::SetNeedsRedraw() {
 
 ManagedMemoryPolicy LayerTreeHostImpl::ActualManagedMemoryPolicy() const {
   ManagedMemoryPolicy actual = cached_managed_memory_policy_;
-  if (debug_state_.rasterize_only_visible_content) {
+  // TODO(ernstm): The second condition disables pre-painting for all layers
+  // when GPU rasterization is enabled. Once we selectively enable GPU
+  // rasterization per layer, we also need to disable pre-painting selectively:
+  // crbug.com/335387
+  if (debug_state_.rasterize_only_visible_content ||
+      settings_.gpu_rasterization) {
     actual.priority_cutoff_when_visible =
         gpu::MemoryAllocation::CUTOFF_ALLOW_REQUIRED_ONLY;
   }