Merge pull request #2227 from nvmkuruc/pcpuserobin

Replace `boost::unordered_map` with `std::unordered_map` in `pxr/usd/pcp/layerStackRegistry.cpp`

(Internal change: 2284862)

pxr/usd/pcp/layerStackRegistry.cpp

@@ -35,9 +35,8 @@
 
 #include <tbb/queuing_rw_mutex.h>
 
-#include <boost/unordered_map.hpp>
-
 #include <algorithm>
+#include <unordered_map>
 #include <utility>
 
 using std::pair;
@@ -57,16 +56,16 @@ class Pcp_LayerStackRegistryData {
 
  typedef SdfLayerHandleVector Layers;
  typedef PcpLayerStackPtrVector LayerStacks;
- typedef boost::unordered_map<PcpLayerStackIdentifier, PcpLayerStackPtr>
- IdentifierToLayerStack;
- typedef boost::unordered_map<SdfLayerHandle, LayerStacks>
+ typedef std::unordered_map<PcpLayerStackIdentifier, PcpLayerStackPtr,
+  TfHash> IdentifierToLayerStack;
+ typedef std::unordered_map<SdfLayerHandle, LayerStacks, TfHash>
  LayerToLayerStacks;
- typedef boost::unordered_map<PcpLayerStackPtr, Layers>
+ typedef std::unordered_map<PcpLayerStackPtr, Layers, TfHash>
  LayerStackToLayers;
 
- typedef boost::unordered_map<std::string, LayerStacks>
+ typedef std::unordered_map<std::string, LayerStacks, TfHash>
  MutedLayerIdentifierToLayerStacks;
- typedef boost::unordered_map<PcpLayerStackPtr, std::set<std::string> >
+ typedef std::unordered_map<PcpLayerStackPtr, std::set<std::string>, TfHash>
  LayerStackToMutedLayerIdentifiers;
 
  IdentifierToLayerStack identifierToLayerStack;