gpu: Add sync token dependencies to flush metadata.

gpu/gles2_conform_support/egl/context.cc

 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/gles2_conform_support/egl/context.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "gpu/command_buffer/client/gles2_implementation.h"
@@ skipping 205 matching lines @@
 bool Context::IsFenceSyncReleased(uint64_t release) {
   NOTIMPLEMENTED();
   return false;
 }
 
 void Context::SignalSyncToken(const gpu::SyncToken& sync_token,
                               const base::Closure& callback) {
   NOTIMPLEMENTED();
 }
 
-bool Context::CanWaitUnverifiedSyncToken(const gpu::SyncToken* sync_token) {
+void Context::WaitSyncToken(const gpu::SyncToken& sync_token) {}

[dcheng, 2017/03/14 06:53:03]

Is this a NOTIMPLEMENTED kind of thing?

[sunnyps, 2017/03/15 00:03:08]

No, GLES2Implementation might call this. I don't know if WaitSyncToken is ever
called in this configuration, but it's OK to have a NOP implementation for this
method.

Maybe this method should be renamed? piman@ WDYT?

[piman, 2017/03/15 00:30:14]

It could be named something like WaitSyncTokenHint to indicate that it's a hint,
that can be used for scheduling, but doesn't have semantic meaning otherwise, so
it's ok to have it do nothing in some implementations?

[sunnyps, 2017/03/15 00:56:11]

Done.

+
+bool Context::CanWaitUnverifiedSyncToken(const gpu::SyncToken& sync_token) {
   return false;
 }
 
 void Context::ApplyCurrentContext(gl::GLSurface* current_surface) {
   DCHECK(HasService());
   // The current_surface will be the same as
   // the surface of the decoder. We can not DCHECK as there is
   // no accessor.
   if (!WasServiceContextLost()) {
     if (!gl_context_->MakeCurrent(current_surface))
@@ skipping 150 matching lines @@
     return false;
   if (!gl_context_->MakeCurrent(gl_surface)) {
     MarkServiceContextLost();
     return false;
   }
   client_gl_context_->Flush();
   return true;
 }
 
 }  // namespace egl