Refactor compilation dependency handling.

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")
 
 # Because standalone V8 builds are not supported, assume this is part of a
 # Chromium build.
@@ skipping 520 matching lines @@
     "src/code-factory.cc",
     "src/code-factory.h",
     "src/code-stubs.cc",
     "src/code-stubs.h",
     "src/code-stubs-hydrogen.cc",
     "src/code.h",
     "src/codegen.cc",
     "src/codegen.h",
     "src/compilation-cache.cc",
     "src/compilation-cache.h",
+    "src/compilation-dependencies.cc",
+    "src/compilation-dependencies.h",
     "src/compilation-statistics.cc",
     "src/compilation-statistics.h",
     "src/compiler/access-builder.cc",
     "src/compiler/access-builder.h",
     "src/compiler/all-nodes.cc",
     "src/compiler/all-nodes.h",
     "src/compiler/ast-graph-builder.cc",
     "src/compiler/ast-graph-builder.h",
     "src/compiler/ast-loop-assignment-analyzer.cc",
     "src/compiler/ast-loop-assignment-analyzer.h",
@@ skipping 1051 matching lines @@
       sources += [
         "src/d8-debug.cc",
         "$target_gen_dir/d8-js.cc",
       ]
     }
     if (v8_enable_i18n_support) {
       deps += [ "//third_party/icu" ]
     }
   }
 }