Implement Fast Accessor Builder

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index d1e9189a1a7386b2ddbb74186e5f5d26524677c7..e8bba18cb982b394be947374ac591364f4fa85c1 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -638,6 +638,7 @@ source_set("v8_base") {
 
   sources = [
     "include/v8-debug.h",
+    "include/v8-experimental.h",
     "include/v8-platform.h",
     "include/v8-profiler.h",
     "include/v8-testing.h",
@@ -655,6 +656,8 @@ source_set("v8_base") {
     "src/allocation-site-scopes.h",
     "src/api.cc",
     "src/api.h",
+    "src/api-experimental.cc",
+    "src/api-experimental.h",
     "src/api-natives.cc",
     "src/api-natives.h",
     "src/arguments.cc",
@@ -764,6 +767,8 @@ source_set("v8_base") {
     "src/compiler/escape-analysis.h",
     "src/compiler/escape-analysis-reducer.cc",
     "src/compiler/escape-analysis-reducer.h",
+    "src/compiler/fast-accessor-assembler.cc",
+    "src/compiler/fast-accessor-assembler.h",
     "src/compiler/frame.cc",
     "src/compiler/frame.h",
     "src/compiler/frame-elider.cc",