[crankshaft] Remove the useless HAllocateBlockContext instruction.

src/crankshaft/x87/lithium-x87.h

Index: src/crankshaft/x87/lithium-x87.h
diff --git a/src/crankshaft/x87/lithium-x87.h b/src/crankshaft/x87/lithium-x87.h
index 58a2b93bcaca8a84469fa41d58328b1e5fc0ce8f..0f2813f85a0a88980ed02fc4ddce7175ac14acad 100644
--- a/src/crankshaft/x87/lithium-x87.h
+++ b/src/crankshaft/x87/lithium-x87.h
@@ -24,7 +24,6 @@ class LCodeGen;
 #define LITHIUM_CONCRETE_INSTRUCTION_LIST(V) \
   V(AccessArgumentsAt)                       \
   V(AddI)                                    \
-  V(AllocateBlockContext)                    \
   V(Allocate)                                \
   V(ApplyArguments)                          \
   V(ArgumentsElements)                       \
@@ -2573,23 +2572,6 @@ class LStoreFrameContext: public LTemplateInstruction<0, 1, 0> {
 };
 
 
-class LAllocateBlockContext: public LTemplateInstruction<1, 2, 0> {
- public:
-  LAllocateBlockContext(LOperand* context, LOperand* function) {
-    inputs_[0] = context;
-    inputs_[1] = function;
-  }
-
-  LOperand* context() { return inputs_[0]; }
-  LOperand* function() { return inputs_[1]; }
-
-  Handle<ScopeInfo> scope_info() { return hydrogen()->scope_info(); }
-
-  DECLARE_CONCRETE_INSTRUCTION(AllocateBlockContext, "allocate-block-context")
-  DECLARE_HYDROGEN_ACCESSOR(AllocateBlockContext)
-};
-
-
 class LChunkBuilder;
 class LPlatformChunk final : public LChunk {
  public: