Add full TurboFan support for accessing SeqString contents.

src/runtime/runtime.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/zone.h"
@@ skipping 629 matching lines @@
   F(IsConstructCall, 0, 1)                                  \
   F(CallFunction, -1 /* receiver + n args + function */, 1) \
   F(DefaultConstructorCallSuper, 0, 1)                      \
   F(ArgumentsLength, 0, 1)                                  \
   F(Arguments, 1, 1)                                        \
   F(ValueOf, 1, 1)                                          \
   F(SetValueOf, 2, 1)                                       \
   F(DateField, 2 /* date object, field index */, 1)         \
   F(StringCharFromCode, 1, 1)                               \
   F(StringCharAt, 2, 1)                                     \
+  F(OneByteSeqStringGetChar, 2, 1)                          \
   F(OneByteSeqStringSetChar, 3, 1)                          \
+  F(TwoByteSeqStringGetChar, 2, 1)                          \
   F(TwoByteSeqStringSetChar, 3, 1)                          \
   F(ObjectEquals, 2, 1)                                     \
   F(IsObject, 1, 1)                                         \
   F(IsFunction, 1, 1)                                       \
   F(IsUndetectableObject, 1, 1)                             \
   F(IsSpecObject, 1, 1)                                     \
   F(IsStringWrapperSafeForDefaultValueOf, 1, 1)             \
   F(MathPow, 2, 1)                                          \
   F(IsMinusZero, 1, 1)                                      \
   F(HasCachedArrayIndex, 1, 1)                              \
@@ skipping 241 matching lines @@
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 STATIC_ASSERT(LANGUAGE_END == 3);
 class DeclareGlobalsLanguageMode : public BitField<LanguageMode, 2, 2> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_