Makes tile-creation lazy

cc/resources/picture_layer_tiling_set_unittest.cc

Index: cc/resources/picture_layer_tiling_set_unittest.cc
diff --git a/cc/resources/picture_layer_tiling_set_unittest.cc b/cc/resources/picture_layer_tiling_set_unittest.cc
index d2af09ae904218f265e51855945d7680735f5ab3..1cc552d269ae4257b9541f3f6f69649e3b8473bc 100644
--- a/cc/resources/picture_layer_tiling_set_unittest.cc
+++ b/cc/resources/picture_layer_tiling_set_unittest.cc
@@ -19,11 +19,9 @@ namespace {
 
 TEST(PictureLayerTilingSetTest, NoResources) {
   FakePictureLayerTilingClient client;
-  PictureLayerTilingSet set(&client);
-  client.SetTileSize(gfx::Size(256, 256));
-
   gfx::Size layer_bounds(1000, 800);
-  set.SetLayerBounds(layer_bounds);
+  PictureLayerTilingSet set(&client, layer_bounds);
+  client.SetTileSize(gfx::Size(256, 256));
 
   set.AddTiling(1.0);
   set.AddTiling(1.5);
@@ -67,14 +65,13 @@ class PictureLayerTilingSetTestWithResources : public testing::Test {
 
     FakePictureLayerTilingClient client;
     client.SetTileSize(gfx::Size(256, 256));
-    PictureLayerTilingSet set(&client);
-
     gfx::Size layer_bounds(1000, 800);
-    set.SetLayerBounds(layer_bounds);
+    PictureLayerTilingSet set(&client, layer_bounds);
 
     float scale = min_scale;
     for (int i = 0; i < num_tilings; ++i, scale += scale_increment) {
       PictureLayerTiling* tiling = set.AddTiling(scale);
+      tiling->CreateAllTilesForTesting();
       std::vector<Tile*> tiles = tiling->AllTilesForTesting();
       for (size_t i = 0; i < tiles.size(); ++i) {
         EXPECT_FALSE(tiles[i]->drawing_info().GetResourceForTesting());