[crankshaft] Delete unused Hydrogen-BCH code

tools/gyp/v8.gyp

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 727 matching lines @@
         '../../src/conversions-inl.h',
         '../../src/conversions.cc',
         '../../src/conversions.h',
         '../../src/counters.cc',
         '../../src/counters.h',
         '../../src/crankshaft/compilation-phase.cc',
         '../../src/crankshaft/compilation-phase.h',
         '../../src/crankshaft/hydrogen-alias-analysis.h',
         '../../src/crankshaft/hydrogen-bce.cc',
         '../../src/crankshaft/hydrogen-bce.h',
-        '../../src/crankshaft/hydrogen-bch.cc',
-        '../../src/crankshaft/hydrogen-bch.h',
         '../../src/crankshaft/hydrogen-canonicalize.cc',
         '../../src/crankshaft/hydrogen-canonicalize.h',
         '../../src/crankshaft/hydrogen-check-elimination.cc',
         '../../src/crankshaft/hydrogen-check-elimination.h',
         '../../src/crankshaft/hydrogen-dce.cc',
         '../../src/crankshaft/hydrogen-dce.h',
         '../../src/crankshaft/hydrogen-dehoist.cc',
         '../../src/crankshaft/hydrogen-dehoist.h',
         '../../src/crankshaft/hydrogen-environment-liveness.cc',
         '../../src/crankshaft/hydrogen-environment-liveness.h',
@@ skipping 1519 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }