[wasm] Decoding the names section should stop if there is a problem with locals.

src/wasm/decoder.h

 // Copyright 2015 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_WASM_DECODER_H_
 #define V8_WASM_DECODER_H_
 
 #include <memory>
 
 #include "src/base/compiler-specific.h"
@@ skipping 364 matching lines @@
       while (pc_ < end) {
         b = *pc_++;
         TRACE("%02x ", b);
         result = result | (static_cast<IntType>(b & 0x7F) << shift);
         shift += 7;
         if ((b & 0x80) == 0) break;
       }
 
       int length = static_cast<int>(pc_ - pos);
       if (pc_ == end && (b & 0x80)) {
+        TRACE("\n");
         error(pc_ - 1, "varint too large");
       } else if (length == 0) {
+        TRACE("\n");
         error(pc_, "varint of length 0");
       } else if (is_signed) {
         if (length < kMaxLength) {
           int sign_ext_shift = 8 * sizeof(IntType) - shift;
           // Perform sign extension.
           result = (result << sign_ext_shift) >> sign_ext_shift;
         }
         TRACE("= %" PRIi64 "\n", static_cast<int64_t>(result));
       } else {
         TRACE("= %" PRIu64 "\n", static_cast<uint64_t>(result));
       }
       return result;
     }
     return traceOffEnd<uint32_t>();
   }
 };
 
 #undef TRACE
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_DECODER_H_