gpu: Add GpuFence framework.

content/browser/gpu/browser_gpu_memory_buffer_manager.cc

Index: content/browser/gpu/browser_gpu_memory_buffer_manager.cc
diff --git a/content/browser/gpu/browser_gpu_memory_buffer_manager.cc b/content/browser/gpu/browser_gpu_memory_buffer_manager.cc
index 51aeb5eb39c59bb465d77a6da4b2453df8d4affe..4bb1461fbe2a1a14b138232ef3a25085644a7b55 100644
--- a/content/browser/gpu/browser_gpu_memory_buffer_manager.cc
+++ b/content/browser/gpu/browser_gpu_memory_buffer_manager.cc
@@ -20,6 +20,7 @@
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
 #include "gpu/GLES2/gl2extchromium.h"
+#include "gpu/ipc/client/gpu_fence_impl.h"
 #include "gpu/ipc/client/gpu_memory_buffer_impl.h"
 #include "gpu/ipc/client/gpu_memory_buffer_impl_shared_memory.h"
 #include "gpu/ipc/common/gpu_memory_buffer_support.h"
@@ -298,6 +299,22 @@ void BrowserGpuMemoryBufferManager::SetDestructionSyncToken(
       sync_token);
 }
 
+std::unique_ptr<gfx::GpuFence> BrowserGpuMemoryBufferManager::CreateGpuFence() {
+  std::unique_ptr<gpu::GpuFenceImpl> fence(new gpu::GpuFenceImpl);
+  return std::move(fence);
+}
+
+std::unique_ptr<gfx::GpuFence>
+BrowserGpuMemoryBufferManager::CreateGpuFenceFromHandle(
+    const gfx::GpuFenceHandle& handle) {
+  return nullptr;
+}
+
+gfx::GpuFence* BrowserGpuMemoryBufferManager::GpuFenceFromClientFence(
+    ClientFence fence) {
+  return gpu::GpuFenceImpl::FromClientFence(fence);
+}
+
 bool BrowserGpuMemoryBufferManager::OnMemoryDump(
     const base::trace_event::MemoryDumpArgs& args,
     base::trace_event::ProcessMemoryDump* pmd) {
@@ -351,6 +368,14 @@ void BrowserGpuMemoryBufferManager::ChildProcessDeletedGpuMemoryBuffer(
   DestroyGpuMemoryBufferOnIO(id, child_client_id, sync_token);
 }
 
+void BrowserGpuMemoryBufferManager::CreateGpuFenceForChildProcess(
+    base::ProcessHandle child_process_handle,
+    const FenceCreationCallback& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  callback.Run(gpu::GpuFenceImpl::CreateForChildProcess(child_process_handle));
+}
+
 void BrowserGpuMemoryBufferManager::ProcessRemoved(
     base::ProcessHandle process_handle,
     int client_id) {