[crankshaft] Delete unused Hydrogen-BCH code

BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/mips.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
 if (is_android) {
@@ skipping 900 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 1163 matching lines @@
 
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [ "//build/config/compiler:no_chromium_code" ]
   configs += [
     ":internal_config",
     ":libplatform_config",
     ":features",
     ":toolchain",
   ]
 }