Re-land: cc: Examine layers to determine if we're ready to activate.

cc/layers/picture_layer_impl_unittest.cc

Index: cc/layers/picture_layer_impl_unittest.cc
diff --git a/cc/layers/picture_layer_impl_unittest.cc b/cc/layers/picture_layer_impl_unittest.cc
index d919298d97106c61a9f32a2feeb199af0258087b..64454aec33a35c0fad2eb51780ce7a85be821007 100644
--- a/cc/layers/picture_layer_impl_unittest.cc
+++ b/cc/layers/picture_layer_impl_unittest.cc
@@ -2391,5 +2391,61 @@ TEST_F(PictureLayerImplTest, RasterScaleChangeWithoutAnimation) {
   EXPECT_BOTH_EQ(HighResTiling()->contents_scale(), 1.f);
 }
 
+TEST_F(PictureLayerImplTest, LowResReadyToDrawNotEnoughToActivate) {
+  gfx::Size tile_size(100, 100);
+  gfx::Size layer_bounds(1000, 1000);
+
+  SetupDefaultTreesWithFixedTileSize(layer_bounds, tile_size);
+
+  // Make sure some tiles are not shared.
+  pending_layer_->set_invalidation(gfx::Rect(gfx::Point(50, 50), tile_size));
+
+  CreateHighLowResAndSetAllTilesVisible();
+  active_layer_->SetAllTilesReady();
+  pending_layer_->MarkVisibleResourcesAsRequired();
+
+  // All pending layer tiles required are not ready.
+  EXPECT_FALSE(pending_layer_->AllTilesRequiredForActivationAreReadyToDraw());
+
+  // Initialize all low-res tiles.
+  pending_layer_->SetAllTilesReadyInTiling(pending_layer_->LowResTiling());
+
+  // Low-res tiles should not be enough.
+  EXPECT_FALSE(pending_layer_->AllTilesRequiredForActivationAreReadyToDraw());
+
+  // Initialize remaining tiles.
+  pending_layer_->SetAllTilesReady();
+
+  EXPECT_TRUE(pending_layer_->AllTilesRequiredForActivationAreReadyToDraw());
+}
+
+TEST_F(PictureLayerImplTest, HighResReadyToDrawNotEnoughToActivate) {
+  gfx::Size tile_size(100, 100);
+  gfx::Size layer_bounds(1000, 1000);
+
+  SetupDefaultTreesWithFixedTileSize(layer_bounds, tile_size);
+
+  // Make sure some tiles are not shared.
+  pending_layer_->set_invalidation(gfx::Rect(gfx::Point(50, 50), tile_size));
+
+  CreateHighLowResAndSetAllTilesVisible();
+  active_layer_->SetAllTilesReady();
+  pending_layer_->MarkVisibleResourcesAsRequired();
+
+  // All pending layer tiles required are not ready.
+  EXPECT_FALSE(pending_layer_->AllTilesRequiredForActivationAreReadyToDraw());
+
+  // Initialize all high-res tiles.
+  pending_layer_->SetAllTilesReadyInTiling(pending_layer_->HighResTiling());
+
+  // High-res tiles should not be enough.
+  EXPECT_FALSE(pending_layer_->AllTilesRequiredForActivationAreReadyToDraw());
+
+  // Initialize remaining tiles.
+  pending_layer_->SetAllTilesReady();
+
+  EXPECT_TRUE(pending_layer_->AllTilesRequiredForActivationAreReadyToDraw());
+}
+
 }  // namespace
 }  // namespace cc