Implement new Function.prototype.toString and fix CreateDynamicFunction parsing

src/api.cc

 // 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.
 
 #include "src/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 2244 matching lines @@
   if (!source->resource_name.IsEmpty()) {
     name_obj = Utils::OpenHandle(*(source->resource_name));
   }
   if (!source->resource_line_offset.IsEmpty()) {
     line_offset = static_cast<int>(source->resource_line_offset->Value());
   }
   if (!source->resource_column_offset.IsEmpty()) {
     column_offset = static_cast<int>(source->resource_column_offset->Value());
   }
   i::Handle<i::JSFunction> fun;
+  // TODO(jwolfe): restrict parameters_end_pos?

[Dan Ehrenberg, 2016/12/06 00:32:13]

Could you elaborate a bit more in this TODO? Why would you restrict it, and what
effect would that have?

[jwolfe, 2017/01/13 00:28:47]

I just did it, and it seems like the right thing to do.

What this means is that mismatched parentheses or backticks will cause a syntax
error through this API just like they do for CreateDynamicFunction().

   has_pending_exception =
       !i::Compiler::GetFunctionFromEval(
            source_string, outer_info, context, i::SLOPPY,
-           i::ONLY_SINGLE_FUNCTION_LITERAL, eval_scope_position, eval_position,
-           line_offset, column_offset - scope_position, name_obj,
-           source->resource_options)
+           i::ONLY_SINGLE_FUNCTION_LITERAL, i::kNoSourcePosition,
+           eval_scope_position, eval_position, line_offset,
+           column_offset - scope_position, name_obj, source->resource_options)
            .ToHandle(&fun);
   if (has_pending_exception) {
     isolate->ReportPendingMessages();
   }
   RETURN_ON_FAILED_EXECUTION(Function);
 
   i::Handle<i::Object> result;
   has_pending_exception =
       !i::Execution::Call(isolate, fun,
                           Utils::OpenHandle(*v8_context->Global()), 0,
@@ skipping 7583 matching lines @@
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 }  // namespace internal
 }  // namespace v8