Add a pretty printer to improve the error message non-function calls

src/runtime/runtime-debug.cc

Index: src/runtime/runtime-debug.cc
diff --git a/src/runtime/runtime-debug.cc b/src/runtime/runtime-debug.cc
index 12c5a0d84f3567a2690bdd0fb1e6bee107f6e81d..5663a58f356a308bf347b188a8e492926c9b55ec 100644
--- a/src/runtime/runtime-debug.cc
+++ b/src/runtime/runtime-debug.cc
@@ -9,7 +9,9 @@
 #include "src/debug.h"
 #include "src/deoptimizer.h"
 #include "src/isolate-inl.h"
+#include "src/messages.h"
 #include "src/parser.h"
+#include "src/prettyprinter.h"
 #include "src/runtime/runtime.h"
 #include "src/runtime/runtime-utils.h"
 
@@ -2727,6 +2729,21 @@ RUNTIME_FUNCTION(Runtime_GetScript) {
 }
 
 
+RUNTIME_FUNCTION(Runtime_RenderCallSite) {

[Yang, 2015/01/20 08:19:07]

Nit: runtime-debug.cc is used for debugger related stuff. This would belong to
runtime-internal.cc where the other stack trace and message related stuff are.

+  HandleScope scope(isolate);
+  DCHECK(args.length() == 0);
+  MessageLocation location;
+  isolate->ComputeLocation(&location);
+  if (location.start_pos() == -1) return isolate->heap()->empty_string();
+  CompilationInfoWithZone info(location.script());

[Yang, 2015/01/20 08:19:07]

If you could get the JSFunction from within ComputeLocation, and use it to
create the CompilationInfo, I'd imagine that parsing and ast visiting can go
quite a lot faster since you would only be creating AST for that particular
function.

+  if (!Parser::Parse(&info)) return isolate->heap()->empty_string();
+  Zone zone(isolate);
+  CallPrinter printer(&zone);
+  const char* string = printer.Print(info.function(), location.start_pos());
+  return *isolate->factory()->NewStringFromAsciiChecked(string);
+}
+
+
 // Check whether debugger and is about to step into the callback that is passed
 // to a built-in function such as Array.forEach.
 RUNTIME_FUNCTION(Runtime_DebugCallbackSupportsStepping) {