Update from https://crrev.com/304418

cc/test/fake_picture_pile_impl.cc

Index: cc/test/fake_picture_pile_impl.cc
diff --git a/cc/test/fake_picture_pile_impl.cc b/cc/test/fake_picture_pile_impl.cc
index 3d31c12a0f65864e7f748d0cac6bb971de05051a..cb68e87bfc8367fe5351ea91a6ae74384234d0f5 100644
--- a/cc/test/fake_picture_pile_impl.cc
+++ b/cc/test/fake_picture_pile_impl.cc
@@ -8,6 +8,7 @@
 #include <limits>
 #include <utility>
 
+#include "base/synchronization/waitable_event.h"
 #include "cc/resources/picture_pile.h"
 #include "cc/test/fake_picture_pile.h"
 #include "cc/test/impl_side_painting_settings.h"
@@ -15,10 +16,14 @@
 
 namespace cc {
 
-FakePicturePileImpl::FakePicturePileImpl() {}
+FakePicturePileImpl::FakePicturePileImpl() : playback_allowed_event_(nullptr) {
+}
 
-FakePicturePileImpl::FakePicturePileImpl(const PicturePile* other)
+FakePicturePileImpl::FakePicturePileImpl(
+    const PicturePile* other,
+    base::WaitableEvent* playback_allowed_event)
     : PicturePileImpl(other),
+      playback_allowed_event_(playback_allowed_event),
       tile_grid_info_(other->GetTileGridInfoForTesting()) {
 }
 
@@ -34,7 +39,7 @@ scoped_refptr<FakePicturePileImpl> FakePicturePileImpl::CreateFilledPile(
   pile.SetRecordedViewport(gfx::Rect(layer_bounds));
   pile.SetHasAnyRecordings(true);
 
-  auto pile_impl = make_scoped_refptr(new FakePicturePileImpl(&pile));
+  auto pile_impl = make_scoped_refptr(new FakePicturePileImpl(&pile, nullptr));
   for (int x = 0; x < pile_impl->tiling().num_tiles_x(); ++x) {
     for (int y = 0; y < pile_impl->tiling().num_tiles_y(); ++y)
       pile_impl->AddRecordingAt(x, y);
@@ -51,7 +56,7 @@ scoped_refptr<FakePicturePileImpl> FakePicturePileImpl::CreateEmptyPile(
   pile.SetTileGridSize(ImplSidePaintingSettings().default_tile_grid_size);
   pile.SetRecordedViewport(gfx::Rect());
   pile.SetHasAnyRecordings(false);
-  return make_scoped_refptr(new FakePicturePileImpl(&pile));
+  return make_scoped_refptr(new FakePicturePileImpl(&pile, nullptr));
 }
 
 scoped_refptr<FakePicturePileImpl>
@@ -65,7 +70,7 @@ FakePicturePileImpl::CreateEmptyPileThatThinksItHasRecordings(
   // This simulates a false positive for this flag.
   pile.SetRecordedViewport(gfx::Rect());
   pile.SetHasAnyRecordings(true);
-  return make_scoped_refptr(new FakePicturePileImpl(&pile));
+  return make_scoped_refptr(new FakePicturePileImpl(&pile, nullptr));
 }
 
 scoped_refptr<FakePicturePileImpl>
@@ -79,11 +84,26 @@ FakePicturePileImpl::CreateInfiniteFilledPile() {
   pile.SetRecordedViewport(gfx::Rect(size));
   pile.SetHasAnyRecordings(true);
 
-  auto pile_impl = make_scoped_refptr(new FakePicturePileImpl(&pile));
+  auto pile_impl = make_scoped_refptr(new FakePicturePileImpl(&pile, nullptr));
   pile_impl->AddRecordingAt(0, 0);
   return pile_impl;
 }
 
+scoped_refptr<FakePicturePileImpl> FakePicturePileImpl::CreateFromPile(
+    const PicturePile* other,
+    base::WaitableEvent* playback_allowed_event) {
+  return make_scoped_refptr(
+      new FakePicturePileImpl(other, playback_allowed_event));
+}
+
+void FakePicturePileImpl::PlaybackToCanvas(SkCanvas* canvas,
+                                           const gfx::Rect& canvas_rect,
+                                           float contents_scale) const {
+  if (playback_allowed_event_)
+    playback_allowed_event_->Wait();
+  PicturePileImpl::PlaybackToCanvas(canvas, canvas_rect, contents_scale);
+}
+
 void FakePicturePileImpl::AddRecordingAt(int x, int y) {
   EXPECT_GE(x, 0);
   EXPECT_GE(y, 0);