Simplify double to bigint conversion.

runtime/vm/exceptions.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/exceptions.h"
 
 #include "platform/address_sanitizer.h"
 
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
@@ skipping 679 matching lines @@
       constructor_name = &Symbols::DotWithType();
       break;
     case kFormat:
       library = Library::CoreLibrary();
       class_name = &Symbols::FormatException();
       break;
     case kUnsupported:
       library = Library::CoreLibrary();
       class_name = &Symbols::UnsupportedError();
       break;
-    case kInternalError:
-      library = Library::CoreLibrary();
-      class_name = &Symbols::InternalError();
-      break;
     case kNullThrown:
       library = Library::CoreLibrary();
       class_name = &Symbols::NullThrownError();
       break;
     case kIsolateSpawn:
       library = Library::IsolateLibrary();
       class_name = &Symbols::IsolateSpawnException();
       break;
     case kIsolateUnhandledException:
       library = Library::IsolateLibrary();
@@ skipping 46 matching lines @@
 
 // Throw JavascriptCompatibilityError exception.
 void Exceptions::ThrowJavascriptCompatibilityError(const char* msg) {
   const Array& exc_args = Array::Handle(Array::New(1));
   const String& msg_str = String::Handle(String::New(msg));
   exc_args.SetAt(0, msg_str);
   Exceptions::ThrowByType(Exceptions::kJavascriptCompatibilityError, exc_args);
 }
 
 }  // namespace dart