gpu: Add sync token dependencies to flush metadata.

gpu/ipc/client/command_buffer_proxy_impl.h

Index: gpu/ipc/client/command_buffer_proxy_impl.h
diff --git a/gpu/ipc/client/command_buffer_proxy_impl.h b/gpu/ipc/client/command_buffer_proxy_impl.h
index c35b70090ea7259e52bd461acdc76f78246ae260..2623fb02f559a13486685bfec552a79d5528f9dc 100644
--- a/gpu/ipc/client/command_buffer_proxy_impl.h
+++ b/gpu/ipc/client/command_buffer_proxy_impl.h
@@ -125,7 +125,8 @@ class GPU_EXPORT CommandBufferProxyImpl
   bool IsFenceSyncReleased(uint64_t release) override;
   void SignalSyncToken(const gpu::SyncToken& sync_token,
                        const base::Closure& callback) override;
-  bool CanWaitUnverifiedSyncToken(const gpu::SyncToken* sync_token) override;
+  void WaitSyncToken(const gpu::SyncToken& sync_token) override;
+  bool CanWaitUnverifiedSyncToken(const gpu::SyncToken& sync_token) override;
 
   void TakeFrontBuffer(const gpu::Mailbox& mailbox);
   void ReturnFrontBuffer(const gpu::Mailbox& mailbox,
@@ -260,26 +261,28 @@ class GPU_EXPORT CommandBufferProxyImpl
   const gpu::CommandBufferId command_buffer_id_;
   const int32_t route_id_;
   const int32_t stream_id_;
-  uint32_t flush_count_;
-  int32_t last_put_offset_;
-  int32_t last_barrier_put_offset_;
+  uint32_t flush_count_ = 0;
+  int32_t last_put_offset_ = -1;
+  int32_t last_barrier_put_offset_ = -1;
 
   // Next generated fence sync.
-  uint64_t next_fence_sync_release_;
+  uint64_t next_fence_sync_release_ = 1;
+
+  std::vector<SyncToken> pending_sync_token_dependencies_;
 
   // Unverified flushed fence syncs with their corresponding flush id.
   std::queue<std::pair<uint64_t, uint32_t>> flushed_release_flush_id_;
 
   // Last flushed fence sync release, same as last item in queue if not empty.
-  uint64_t flushed_fence_sync_release_;
+  uint64_t flushed_fence_sync_release_ = 0;
 
   // Last verified fence sync.
-  uint64_t verified_fence_sync_release_;
+  uint64_t verified_fence_sync_release_ = 0;
 
   GpuConsoleMessageCallback console_message_callback_;
 
   // Tasks to be invoked in SignalSyncPoint responses.
-  uint32_t next_signal_id_;
+  uint32_t next_signal_id_ = 0;
   SignalTaskMap signal_tasks_;
 
   gpu::Capabilities capabilities_;