Add frame refresh to VideoCaptureDevice, and buffer pool resurrection.

This is the first in a series of changes to solve the problems related
to VideoCaptureDevices that can pause (i.e., basically, screen capture
devices).  This introduces new optional-to-implement methods to the
media::VideoCaptureDevice interface, and the supporting functionality in
content::VideoCaptureBufferPool.

This change should not result in any end-user-visible differences, as it
is just laying the groundwork for future changes.  For more details on
the overall plan, please see the crbug.

BUG=486274

Review URL: https://codereview.chromium.org/1826643003

Cr-Commit-Position: refs/heads/master@{#383426}

1 files changed, 10 insertions, 1 deletions

diff --git a/content/browser/media/capture/desktop_capture_device_aura_unittest.cc b/content/browser/media/capture/desktop_capture_device_aura_unittest.cc
index 984b661..0bcb066 100644
--- a/content/browser/media/capture/desktop_capture_device_aura_unittest.cc
+++ b/content/browser/media/capture/desktop_capture_device_aura_unittest.cc
@@ -60,6 +60,7 @@ class MockDeviceClient : public media::VideoCaptureDevice::Client {
   MOCK_METHOD0(DoReserveOutputBuffer, void(void));
   MOCK_METHOD0(DoOnIncomingCapturedBuffer, void(void));
   MOCK_METHOD0(DoOnIncomingCapturedVideoFrame, void(void));
+  MOCK_METHOD0(DoResurrectLastOutputBuffer, void(void));
   MOCK_METHOD2(OnError,
                void(const tracked_objects::Location& from_here,
                     const std::string& reason));
@@ -85,7 +86,15 @@ class MockDeviceClient : public media::VideoCaptureDevice::Client {
       const base::TimeTicks& timestamp) override {
     DoOnIncomingCapturedVideoFrame();
   }
-
+  scoped_ptr<Buffer> ResurrectLastOutputBuffer(
+      const gfx::Size& dimensions,
+      media::VideoPixelFormat format,
+      media::VideoPixelStorage storage) override {
+    EXPECT_EQ(media::PIXEL_FORMAT_I420, format);
+    EXPECT_EQ(media::PIXEL_STORAGE_CPU, storage);
+    DoResurrectLastOutputBuffer();
+    return scoped_ptr<Buffer>();
+  }
   double GetBufferPoolUtilization() const override { return 0.0; }
 };