Fix BUILD.gn files and add presubmit step

src/v8.gyp

Index: src/v8.gyp
diff --git a/src/v8.gyp b/src/v8.gyp
index 1b4a46b9f52d4152dcc2acdba0a4aa9a3d9e3ee0..b949532ab1776aba1d76fd739bd2ccf9a5d96b8e 100644
--- a/src/v8.gyp
+++ b/src/v8.gyp
@@ -961,6 +961,7 @@
         'ic/call-optimization.h',
         'ic/handler-compiler.cc',
         'ic/handler-compiler.h',
+        'ic/handler-configuration.h',
         'ic/ic-inl.h',
         'ic/ic-state.cc',
         'ic/ic-state.h',
@@ -1412,6 +1413,8 @@
             'ia32/interface-descriptors-ia32.cc',
             'ia32/macro-assembler-ia32.cc',
             'ia32/macro-assembler-ia32.h',
+            'ia32/simulator-ia32.cc',
+            'ia32/simulator-ia32.h',
             'builtins/ia32/builtins-ia32.cc',
             'compiler/ia32/code-generator-ia32.cc',
             'compiler/ia32/instruction-codes-ia32.h',
@@ -1451,6 +1454,8 @@
             'x87/interface-descriptors-x87.cc',
             'x87/macro-assembler-x87.cc',
             'x87/macro-assembler-x87.h',
+            'x87/simulator-x87.cc',
+            'x87/simulator-x87.h',
             'builtins/x87/builtins-x87.cc',
             'compiler/x87/code-generator-x87.cc',
             'compiler/x87/instruction-codes-x87.h',
@@ -1583,6 +1588,8 @@
             'x64/interface-descriptors-x64.cc',
             'x64/macro-assembler-x64.cc',
             'x64/macro-assembler-x64.h',
+            'x64/simulator-x64.cc',
+            'x64/simulator-x64.h',
             'x64/sse-instr.h',
             'debug/x64/debug-x64.cc',
             'full-codegen/x64/full-codegen-x64.cc',
@@ -1593,6 +1600,7 @@
             'ic/x64/stub-cache-x64.cc',
             'regexp/x64/regexp-macro-assembler-x64.cc',
             'regexp/x64/regexp-macro-assembler-x64.h',
+            'third_party/valgrind/valgrind.h',
           ],
         }],
         ['v8_target_arch=="x64"', {