Separate CodeAssembler and CodeStubAssembler

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index b927c7476fa7cae21c8be6180fe8bf67cb73d8e3..2bf43bbfb9b2a4aac0b54f894c4222cd27896b8b 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -755,6 +755,8 @@ source_set("v8_base") {
     "src/checks.h",
     "src/code-factory.cc",
     "src/code-factory.h",
+    "src/code-stub-assembler.cc",
+    "src/code-stub-assembler.h",
     "src/code-stubs-hydrogen.cc",
     "src/code-stubs.cc",
     "src/code-stubs.h",
@@ -792,11 +794,11 @@ source_set("v8_base") {
     "src/compiler/change-lowering.h",
     "src/compiler/coalesced-live-ranges.cc",
     "src/compiler/coalesced-live-ranges.h",
+    "src/compiler/code-assembler.cc",
+    "src/compiler/code-assembler.h",
     "src/compiler/code-generator-impl.h",
     "src/compiler/code-generator.cc",
     "src/compiler/code-generator.h",
-    "src/compiler/code-stub-assembler.cc",
-    "src/compiler/code-stub-assembler.h",
     "src/compiler/common-node-cache.cc",
     "src/compiler/common-node-cache.h",
     "src/compiler/common-operator-reducer.cc",