cc: fix pre-painting trigger for GPU rasterization

CUTOFF_ALLOW_NICE_TO_HAVE was only triggered for --force-gpu-rasterization.
This patch triggers it when the active or the pending tree uses GPU
rasterization. In case of a transition between CPU and GPU rasterization it
is preferrable to pre-paint less on the CPU rasterized tree (which may
checkerboard) than it is to pre-paint more on the GPU rasterized tree (which
may stall the browser compositor).

This patch depends on https://codereview.chromium.org/270823003/

R=enne@chromium.org, alokp@chromium.org
BUG=368884

Review URL: https://codereview.chromium.org/272033002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269682 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 10 insertions, 10 deletions

diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index 1cd0d05..171880e 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -1770,13 +1770,13 @@ void LayerTreeHostImpl::SetNeedsRedraw() {
 
 ManagedMemoryPolicy LayerTreeHostImpl::ActualManagedMemoryPolicy() const {
   ManagedMemoryPolicy actual = cached_managed_memory_policy_;
-  // TODO(ernstm): NICE_TO_HAVE is currently triggered for forced GPU
-  // rasterization only. Change the trigger to LTHI::UseGpuRasterization, once
-  // that is implemented.
+  bool any_tree_use_gpu_rasterization =
+      (active_tree_ && active_tree_->use_gpu_rasterization()) ||
+      (pending_tree_ && pending_tree_->use_gpu_rasterization());
   if (debug_state_.rasterize_only_visible_content) {
     actual.priority_cutoff_when_visible =
         gpu::MemoryAllocation::CUTOFF_ALLOW_REQUIRED_ONLY;
-  } else if (settings_.gpu_rasterization_forced) {
+  } else if (any_tree_use_gpu_rasterization) {
     actual.priority_cutoff_when_visible =
         gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE;
   }
diff --git a/cc/trees/layer_tree_host_impl_unittest.cc b/cc/trees/layer_tree_host_impl_unittest.cc
index 02f383f..3181410 100644
--- a/cc/trees/layer_tree_host_impl_unittest.cc
+++ b/cc/trees/layer_tree_host_impl_unittest.cc
@@ -5767,9 +5767,9 @@ TEST_F(LayerTreeHostImplTest, MemoryPolicy) {
   int nothing_cutoff_value = ManagedMemoryPolicy::PriorityCutoffToValue(
       gpu::MemoryAllocation::CUTOFF_ALLOW_NOTHING);
 
-  // GPU rasterization should be disabled by default.
-  EXPECT_FALSE(host_impl_->settings().gpu_rasterization_enabled);
-  EXPECT_FALSE(host_impl_->settings().gpu_rasterization_forced);
+  // GPU rasterization should be disabled by default on the tree(s)
+  EXPECT_FALSE(host_impl_->active_tree()->use_gpu_rasterization());
+  EXPECT_TRUE(host_impl_->pending_tree() == NULL);
 
   host_impl_->SetVisible(true);
   host_impl_->SetMemoryPolicy(policy1);
@@ -5784,13 +5784,13 @@ TEST_F(LayerTreeHostImplTest, MemoryPolicy) {
   EXPECT_EQ(policy1.bytes_limit_when_visible, current_limit_bytes_);
   EXPECT_EQ(everything_cutoff_value, current_priority_cutoff_value_);
 
-  // Now enable GPU rasterization and test if we get required only cutoff,
+  // Now enable GPU rasterization and test if we get nice to have cutoff,
   // when visible.
   LayerTreeSettings settings;
-  settings.gpu_rasterization_forced = true;
+  settings.gpu_rasterization_enabled = true;
   host_impl_ = LayerTreeHostImpl::Create(
       settings, this, &proxy_, &stats_instrumentation_, NULL, 0);
-
+  host_impl_->active_tree()->SetUseGpuRasterization(true);
   host_impl_->SetVisible(true);
   host_impl_->SetMemoryPolicy(policy1);
   EXPECT_EQ(policy1.bytes_limit_when_visible, current_limit_bytes_);