Enable C++11. Synch toolchains with Chrome.

src/json-parser.h

 // Copyright 2011 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_JSON_PARSER_H_
 #define V8_JSON_PARSER_H_
 
 #include "src/v8.h"
 
 #include "src/char-predicates-inl.h"
@@ skipping 701 matching lines @@
                                            unibrow::Utf16::TrailSurrogate(c0));
       } else {
         running_hash = StringHasher::AddCharacterCore(running_hash, c0);
       }
       position++;
       if (position >= source_length_) return Handle<String>::null();
       c0 = seq_source_->SeqOneByteStringGet(position);
     } while (c0 != '"');
     int length = position - position_;
     uint32_t hash = (length <= String::kMaxHashCalcLength)
-        ? StringHasher::GetHashCore(running_hash) : length;
+                        ? StringHasher::GetHashCore(running_hash)
+                        : static_cast<uint32_t>(length);
     Vector<const uint8_t> string_vector(
         seq_source_->GetChars() + position_, length);
     StringTable* string_table = isolate()->heap()->string_table();
     uint32_t capacity = string_table->Capacity();
     uint32_t entry = StringTable::FirstProbe(hash, capacity);
     uint32_t count = 1;
     Handle<String> result;
     while (true) {
       Object* element = string_table->KeyAt(entry);
       if (element == isolate()->heap()->undefined_value()) {
@@ skipping 48 matching lines @@
 
   DCHECK_EQ('"', c0_);
   // Advance past the last '"'.
   AdvanceSkipWhitespace();
   return result;
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_JSON_PARSER_H_