Move invalid string length check to the factory.

src/heap.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_HEAP_H_
 #define V8_HEAP_H_
 
 #include <cmath>
 
 #include "src/allocation.h"
@@ skipping 1774 matching lines @@
 
   // Allocate and partially initializes a String.  There are two String
   // encodings: ASCII and two byte.  These functions allocate a string of the
   // given length and set its map and length fields.  The characters of the
   // string are uninitialized.
   MUST_USE_RESULT AllocationResult AllocateRawOneByteString(
       int length, PretenureFlag pretenure);
   MUST_USE_RESULT AllocationResult AllocateRawTwoByteString(
       int length, PretenureFlag pretenure);
 
-  // Allocates and fully initializes a String.  There are two String
-  // encodings: ASCII and two byte. One should choose between the three string
-  // allocation functions based on the encoding of the string buffer used to
-  // initialized the string.
-  //   - ...FromAscii initializes the string from a buffer that is ASCII
-  //     encoded (it does not check that the buffer is ASCII encoded) and the
-  //     result will be ASCII encoded.
-  //   - ...FromUTF8 initializes the string from a buffer that is UTF-8
-  //     encoded.  If the characters are all single-byte characters, the
-  //     result will be ASCII encoded, otherwise it will converted to two
-  //     byte.
-  //   - ...FromTwoByte initializes the string from a buffer that is two-byte
-  //     encoded.  If the characters are all single-byte characters, the
-  //     result will be converted to ASCII, otherwise it will be left as
-  //     two-byte.
-  MUST_USE_RESULT AllocationResult AllocateStringFromUtf8Slow(
-      Vector<const char> str,
-      int non_ascii_start,
-      PretenureFlag pretenure = NOT_TENURED);
-  MUST_USE_RESULT AllocationResult AllocateStringFromTwoByte(
-      Vector<const uc16> str,
-      PretenureFlag pretenure = NOT_TENURED);
-
   bool CreateInitialMaps();
   void CreateInitialObjects();
 
   // Allocates an internalized string in old space based on the character
   // stream.
   MUST_USE_RESULT inline AllocationResult AllocateInternalizedStringFromUtf8(
       Vector<const char> str,
       int chars,
       uint32_t hash_field);
 
@@ skipping 956 matching lines @@
   DisallowHeapAllocation no_allocation;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_