Migrate media/gpu from CancelableCallback to Once/Repeating versions

base::CancelableCallback/Closure is deprecated and show be replaced by
the more explicit Once/Repeating versions. The vast majority of this
directory was already migrated, but a few uses remained. We fix the
remaining uses.

A follow-up cl (crrev.com/c/2506350) will enforce a presubmit for this
deprecation to avoid any future regressions.

Bug: 1142629, 1007807
Change-Id: Idbf9531db7f1bf9ee95d72e6f66f73bcc75eacdf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2560799Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Commit-Queue: Alex Turner <alexmt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#831874}

media/gpu/test/video_player/frame_renderer_dummy.h

@@ -87,7 +87,7 @@ class FrameRendererDummy : public FrameRenderer {
   uint64_t frames_dropped_ GUARDED_BY(renderer_lock_);
 
   // Task that simulates rendering a frame to screen.
-  base::CancelableClosure render_task_;
+  base::CancelableRepeatingClosure render_task_;
   // Thread on which rendering video frames is simulated.
   base::Thread renderer_thread_;
   mutable base::Lock renderer_lock_;

media/gpu/video_encode_accelerator_unittest.cc

@@ -1723,7 +1723,7 @@ class VEAClient : public VEAClientBase {
   // The BitstreamBufferReadyTimeout closure. It is set at each
   // BitstreamBufferReady() call, and cancelled at the next
   // BitstreamBufferReady() or flush callback is called.
-  base::CancelableClosure buffer_ready_timeout_;
+  base::CancelableOnceClosure buffer_ready_timeout_;
 
   // The timestamps for each frame in the order of CreateFrame() invocation.
   base::queue<base::TimeDelta> frame_timestamps_;