ui: Add libsync GLFence implementation.

gpu/ipc/client/gpu_fence_impl.cc

Index: gpu/ipc/client/gpu_fence_impl.cc
diff --git a/gpu/ipc/client/gpu_fence_impl.cc b/gpu/ipc/client/gpu_fence_impl.cc
index 722cf8e7188c4e5896d410dbf5cf973c6c29c7dc..e2508e86144eead9a94fa2a92f20fb133b725301 100644
--- a/gpu/ipc/client/gpu_fence_impl.cc
+++ b/gpu/ipc/client/gpu_fence_impl.cc
@@ -5,15 +5,18 @@
 #include "gpu/ipc/client/gpu_fence_impl.h"
 
 #include "base/logging.h"
-#include "build/build_config.h"
+#include "base/memory/ptr_util.h"
+#include "gpu/ipc/client/gpu_fence_impl_shared_event.h"
+#include "ui/gfx/shared_event.h"
+
+#if defined(OS_LINUX)
+#include "gpu/ipc/client/gpu_fence_impl_libsync.h"
+#endif
 
 namespace gpu {
 
 GpuFenceImpl::GpuFenceImpl() {}
 
-GpuFenceImpl::GpuFenceImpl(const gfx::GpuFenceHandle& handle)
-    : shared_event_(handle.shared_event_handle) {}
-
 GpuFenceImpl::~GpuFenceImpl() {}
 
 // static
@@ -26,26 +29,36 @@ gfx::GpuFenceHandle GpuFenceImpl::CreateForChildProcess(
 }
 
 // static
+std::unique_ptr<GpuFenceImpl> GpuFenceImpl::CreateFromHandle(
+    const gfx::GpuFenceHandle& handle) {
+  if (gfx::SharedEvent::IsHandleValid(handle.shared_event_handle)) {
+    return base::MakeUnique<GpuFenceImplSharedEvent>(
+        handle.shared_event_handle);
+  }
+#if defined(OS_LINUX)
+  if (handle.fd.fd >= 0)
+    return base::MakeUnique<GpuFenceImplLibsync>(handle.fd);
+#endif
+  return nullptr;
+}
+
+// static
 GpuFenceImpl* GpuFenceImpl::FromClientFence(ClientFence fence) {
   return reinterpret_cast<GpuFenceImpl*>(fence);
 }
 
 bool GpuFenceImpl::IsSignaled() {
-  return shared_event_.IsSignaled();
+  NOTIMPLEMENTED();
+  return false;
 }
 
 bool GpuFenceImpl::Wait(const base::TimeDelta& max_time) {
-  return shared_event_.Wait(max_time);
+  NOTIMPLEMENTED();
+  return false;
 }
 
 void GpuFenceImpl::Reset() {
-  return shared_event_.Reset();
-}
-
-gfx::GpuFenceHandle GpuFenceImpl::GetHandle() const {
-  gfx::GpuFenceHandle handle;
-  handle.shared_event_handle = shared_event_.GetHandle();
-  return handle;
+  NOTIMPLEMENTED();
 }
 
 ClientFence GpuFenceImpl::AsClientFence() {