[ui/ws] Acknowledge BeginFrames in FrameGenerator + add tests.

services/ui/ws/frame_generator_unittest.cc

Index: services/ui/ws/frame_generator_unittest.cc
diff --git a/services/ui/ws/frame_generator_unittest.cc b/services/ui/ws/frame_generator_unittest.cc
index b5c9b981ec682f149f161c89b96d513f12d8bd41..e195417f3852b61ecb023bcd01729c9e3b54fe3a 100644
--- a/services/ui/ws/frame_generator_unittest.cc
+++ b/services/ui/ws/frame_generator_unittest.cc
@@ -87,7 +87,7 @@ class FakeCompositorFrameSink : public cc::CompositorFrameSink,
   }
 
   void OnDidFinishFrame(const cc::BeginFrameAck& ack) override {
-    external_begin_frame_source_->DidFinishFrame(this, ack);
+    begin_frame_source_->DidFinishFrame(this, ack);
   }
 
   void SetBeginFrameSource(cc::BeginFrameSource* source) {
@@ -175,6 +175,12 @@ class FrameGeneratorTest : public testing::Test {
     return compositor_frame_sink_->last_metadata();
   }
 
+  const cc::BeginFrameAck& LastBeginFrameAckFromFrameGenerator() {

[Fady Samuel, 2017/03/20 18:33:13]

nit: FromFrameGenerator is a bit redundant given this is a framegenerator
unittest.

[Eric Seckler, 2017/03/21 16:26:04]

Done.

+    return begin_frame_source_->LastAckForObserver(compositor_frame_sink_);
+  }
+
+  ServerWindow* root_window() { return root_window_.get(); }
+
  private:
   FakeCompositorFrameSink* compositor_frame_sink_ = nullptr;
   std::unique_ptr<cc::FakeExternalBeginFrameSource> begin_frame_source_;
@@ -193,6 +199,7 @@ TEST_F(FrameGeneratorTest, OnSurfaceCreated) {
   // FrameGenerator does not request BeginFrames upon creation.
   IssueBeginFrame();
   EXPECT_EQ(0, NumberOfFramesReceived());
+  EXPECT_EQ(cc::BeginFrameAck(), LastBeginFrameAckFromFrameGenerator());
 
   const cc::SurfaceId kArbitrarySurfaceId(
       cc::FrameSinkId(1, 1),
@@ -213,10 +220,44 @@ TEST_F(FrameGeneratorTest, OnSurfaceCreated) {
   EXPECT_EQ(1lu, referenced_surfaces.size());
   EXPECT_EQ(kArbitrarySurfaceId, referenced_surfaces.front());
 
+  cc::BeginFrameAck expected_ack(0, 2, 2, 0, true);
+  EXPECT_EQ(expected_ack, LastBeginFrameAckFromFrameGenerator());
+  EXPECT_EQ(expected_ack, last_metadata.begin_frame_ack);
+
   // FrameGenerator stops requesting BeginFrames after submitting a
   // CompositorFrame.
   IssueBeginFrame();
   EXPECT_EQ(1, NumberOfFramesReceived());
+  EXPECT_EQ(cc::BeginFrameAck(0, 2, 2, 0, true),
+            LastBeginFrameAckFromFrameGenerator());
+}
+
+TEST_F(FrameGeneratorTest, BeginFrameWhileInvisible) {
+  EXPECT_EQ(0, NumberOfFramesReceived());
+
+  // A valid SurfaceInfo is required for BeginFrame processing.
+  const cc::SurfaceId kArbitrarySurfaceId(
+      cc::FrameSinkId(1, 1),
+      cc::LocalSurfaceId(1, base::UnguessableToken::Create()));
+  const cc::SurfaceInfo kArbitrarySurfaceInfo(kArbitrarySurfaceId, 1.0f,
+                                              gfx::Size(100, 100));
+  frame_generator()->OnSurfaceCreated(kArbitrarySurfaceInfo);
+  EXPECT_EQ(0, NumberOfFramesReceived());
+
+  // No frames are produced while invisible but in need of BeginFrames.
+  root_window()->SetVisible(false);
+  IssueBeginFrame();
+  EXPECT_EQ(0, NumberOfFramesReceived());
+  EXPECT_EQ(cc::BeginFrameAck(0, 1, 1, 0, false),
+            LastBeginFrameAckFromFrameGenerator());
+
+  // When visible again, frame is produced.
+  root_window()->SetVisible(true);
+  IssueBeginFrame();
+  EXPECT_EQ(1, NumberOfFramesReceived());
+  cc::BeginFrameAck expected_ack(0, 2, 2, 0, true);
+  EXPECT_EQ(expected_ack, LastBeginFrameAckFromFrameGenerator());
+  EXPECT_EQ(expected_ack, LastMetadata().begin_frame_ack);
 }
 
 TEST_F(FrameGeneratorTest, SetDeviceScaleFactor) {