Implemented new fence syncs which replaces the old sync points.

gpu/command_buffer/client/cmd_buffer_helper.cc

Index: gpu/command_buffer/client/cmd_buffer_helper.cc
diff --git a/gpu/command_buffer/client/cmd_buffer_helper.cc b/gpu/command_buffer/client/cmd_buffer_helper.cc
index 35805fe195703e37b006a0b7e2aef33439d0d333..4267eb76689080ea2c32ca407c196e1f91279883 100644
--- a/gpu/command_buffer/client/cmd_buffer_helper.cc
+++ b/gpu/command_buffer/client/cmd_buffer_helper.cc
@@ -31,6 +31,8 @@ CommandBufferHelper::CommandBufferHelper(CommandBuffer* command_buffer)
       token_(0),
       put_(0),
       last_put_sent_(0),
+      next_fence_sync_release_(1),
+      flushed_fence_sync_release_(0),
 #if defined(CMD_HELPER_PERIODIC_FLUSH_CHECK)
       commands_issued_(0),
 #endif
@@ -146,6 +148,12 @@ void CommandBufferHelper::FreeRingBuffer() {
   FreeResources();
 }
 
+uint32_t CommandBufferHelper::GenerateFenceSyncRelease() {
+  // Enforce fence syncs generated are always inserted in the command buffer.
+  const uint32_t release = next_fence_sync_release_++;
+  return release;
+}
+
 bool CommandBufferHelper::Initialize(int32 ring_buffer_size) {
   ring_buffer_size_ = ring_buffer_size;
   return AllocateRingBuffer();
@@ -176,6 +184,8 @@ void CommandBufferHelper::Flush() {
     command_buffer_->Flush(put_);
     ++flush_generation_;
     CalcImmediateEntries(0);
+
+    flushed_fence_sync_release_ = next_fence_sync_release_ - 1;
   }
 }